5th gen 4Runner Mods.

[Telescopist]

Originally Posted by jeffrow

Thank you for the detailed response.

I have read some scare stories about trans temperature that described some scary stuff at 240-260 regarding damage to fluid and transmissions. This may be old school out of date info afaik given the synthetic modern fluids.

I did ask the Toyota service manager about the transmission fluid. That is all they use is a synthetic. It doesn't break down nearly as much when experiencing higher temperatures. The how high and when does it break down is another question or questions.

I'm considering installing an additional cooler with a thermostatically controlled fan so I don't stress about this too much.
Thanks again.

If you do that would you please report back? Thanks

[Viajante]

Originally Posted by jeffrow

My unknown is that there are supposed to be 2 tranny temp measurement points in the Toyota 5sp auto. One at or near the return in the pan, the other immediately after the torque converter. Only one of the pids I found for the scanguage worked for me when I set it up. I speculate that the point I am measuring is at the torque converter because the temp jumps immediately when the transmission unlocks and drops fairly quickly when it re-locks.

I was able to read both sensors in my 4th gen 4Runner using the Torque Pro app. You are correct that you are reading the temperature spike between the torque converter and the cooler. When you hear/feel the transmission unlock you can downshift to lock the transmission in the next lowest gear and the temp will drop.

I don't know how long the transmission fluid has to be above 250F for it to be damaged. Maybe the spikes aren't all that important, but I don't know. On a 4Runner website it was reported that the transmission warning light comes on at 302F.

I added a transmission cooler but I concluded that it really wasn't necessary.

[jeffrow]

Originally Posted by Telescopist

I did ask the Toyota service manager about the transmission fluid. That is all they use is a synthetic. It doesn't break down nearly as much when experiencing higher temperatures. The how high and when does it break down is another question or questions.



If you do that would you please report back? Thanks

Thanks and will do on the cooler.

[jeffrow]

Originally Posted by Viajante

I was able to read both sensors in my 4th gen 4Runner using the Torque Pro app. You are correct that you are reading the temperature spike between the torque converter and the cooler. When you hear/feel the transmission unlock you can downshift to lock the transmission in the next lowest gear and the temp will drop.

I don't know how long the transmission fluid has to be above 250F for it to be damaged. Maybe the spikes aren't all that important, but I don't know. On a 4Runner website it was reported that the transmission warning light comes on at 302F.

I added a transmission cooler but I concluded that it really wasn't necessary.

On my transmission only 4 and 5th lock up.

In re warning light.... 302f is the highest of many temps I have read. Some as low as 240-250f. Thats why my concern, if 302f is the real number I would be much relieved.

[Viajante]

Originally Posted by jeffrow

On my transmission only 4 and 5th lock up.

In re warning light.... 302f is the highest of many temps I have read. Some as low as 240-250f. Thats why my concern, if 302f is the real number I would be much relieved.

Yes, there are quite a few opinions as to when the transmission fluid is damaged. The 302F is the first I saw that refers to when the transmission light on the dash comes on.

As far as your scan picking up only one sensor, not a problem since you are getting the "hot" reading. Whatever temp you see the fluid cool down to after the spike is the temp reading of the other sensor. When the transmission is locked the two sensor readings are in sync.

[Telescopist]

Originally Posted by Viajante

As far as your scan picking up only one sensor, not a problem since you are getting the "hot" reading. Whatever temp you see the fluid cool down to after the spike is the temp reading of the other sensor. When the transmission is locked the two sensor readings are in sync.

Just to clear up my own confusion when is the transmission in locked mode?

[Brian B-P]

Originally Posted by Telescopist

I just had a fairly lengthy (15 minutes) conversation with the head of the service department at my local Toyota dealership. Basically he said that the warranty is not voided by adding an auxiliary cooler UNLESS it is found that the cooler was the cause of the failure. What they would do is some sort of forensic (my word) examination of the transmission, the cooler, and anything in between. Then they would contact the Toyota Technical Experience Center and consult with them. The TTEC has the final word of course.

A good service manager! Yes, that's how warranties work - ignore people who say that if you do anything to the vehicle it voids the warranty entirely, even for unrelated components and failures.

Originally Posted by Telescopist

He did say that they rarely run into situations where the transmissions on these vehicles actually fail. He seemed to be saying that the transmission is pretty reliable and robust.

The 4Runner still has a 5-speed automatic. That's not just a bit behind - it's wildly out of date in 2019. Toyota has transmissions which are used with the same series of engine and would presumably fit the 4Runner with 6 speeds (in trucks) and 8 speeds (in cars). It is possible that they still put the 5-speed (A750F) in the 4Runner because it has proven to be durable; however, it's likely that the 4Runner is just waiting for an update to get the 6-speeds or 8-speeds, since other Toyota models with similar chassis design (and similar or more powerful engines) have switched to six-speed transmissions since the last 4Runner design update. Whatever the reason, that 5-speed is a long-proven transmission.

[Viajante]

Originally Posted by Telescopist

Just to clear up my own confusion when is the transmission in locked mode?

The transmission is locked when the gears are physically connected to the drive shaft, as in a linkage that has no slippage. When the engine needs more power, as when the vehicle goes up an incline, the transmission will unlock and power will be transferred to the gears via the torque converter, which is a hydraulic coupling. As the torque converter spins to generate power it churns up the transmission fluid and heats it up.

If even more power is needed the vehicle will downshift and the transmission will lock into a lower gear. The torque converter stops churning and the fluid cools back down.

When the transmission goes into torque it sounds and feels like a downshift, you pick up a few hundred rpm and get a power surge. But, it is really sort of a half shift.

Brian can tackle this one better.

[Telescopist]

Originally Posted by Viajante

The transmission is locked when the gears are physically connected to the drive shaft, as in a linkage that has no slippage. When the engine needs more power, as when the vehicle goes up an incline, the transmission will unlock and power will be transferred to the gears via the torque converter, which is a hydraulic coupling. As the torque converter spins to generate power it churns up the transmission fluid and heats it up.

If even more power is needed the vehicle will downshift and the transmission will lock into a lower gear. The torque converter stops churning and the fluid cools back down.

When the transmission goes into torque it sounds and feels like a downshift, you pick up a few hundred rpm and get a power surge. But, it is really sort of a half shift.

Brian can tackle this one better.

Appreciate the explanation. I am ignorant about these things.

[Telescopist]

Whatever the reason, that 5-speed is a long-proven transmission.

You are a veritable fountain of knowledge. I will have to suffer through having this antiquated 5-speed transmission. Particularly in light of the fact that the price I paid for it put a huge hit on my checking account.:

It may be wishful thinking but it seemed to me that the service manager was saying the same thing: the 5-speed has survived the test of time.

[Brian B-P]

Originally Posted by Viajante

Brian can tackle this one better.

Not really - I think that was very clear.

I'll just note that the torque converter isn't just a fluid coupling - it actually does multiply torque by a variable ratio, like an adjustable stage of reduction gearing, which isn't very efficient but can allow the transmission to produce more torque output from the same input, although the engine must run faster to do that.

As Viajante noted, this means that using the torque converter is much like shifting part-way to the next lower gear. That means that transmissions which have more ratios (speeds, gears) don't need to use the torque converter as much; the current 8-speed and 10-speed transmissions basically don't use the torque converter except to start from a standstill, when the slippage is needed to keep the engine from stalling.

[Telescopist]

Originally Posted by BRietkerk

The 4 Runner has the 7 pin connector under the left side of the bumper. ETI should be reminded that this requires a longer made up 7 pin cable than they install as standard. When we started towing with our 2016 limited 4 Runner I had to buy a longer cable to replace the original. I did not want to add a junction box or a splice.
Cables are made up in two standard lengths. I purchased the long version at a local RV dealer.
You may want to advise ETI the measurement from 7 pin receptacle to ball on your TV.

I received this response from Escape regarding the the 7 pin cable. "Interesting. I haven’t heard of this before. I just measured our cable on the 21’ and it extends 40” past the ball coupler."

[BRietkerk]

Good to hear ETI made the change to the long cable version as standard. There was a discussion on the forum in the past regarding 4 Runner owners who had to find ways to connect. Todays buyers benefit from the many improvements made over the years to the ETI products. I get temped to buy a new version 19 every time I visit.

[Great Eggstrications]

I'm sort of late to this party - been overseas for the past 6 weeks - but had a PM from Telescopist when I got home a few days ago:

I will be picking up my 21 Escape on May 21. I just purchased a 2019 4Runner Limited.

1. Should I go ahead and install a transmission cooler before leaving? If so can you recommend a type?
2. The GCWR according to the manual is 11,300#.
3. It seems from what you wrote that you employ the 'S' option - 3rd gear in ascents and when descending? Is 3rd gear located on the shifting lever?
4. Are the Timbren bump stop / helper springs something you would recommend that I install before I leave for Chilliwack?

1 - I would highly recommend that you install a tranny cooler. The consensus appears to be that a stacked plate type would be better than a tube and fin type - the former has more heat transfer capability for the same size cooler, and things are sort of tight behind the grill.

I installed a B&M 14,400 BTU "SuperCooler" from Jeg's - about 100 bucks currently.

https://www.jegs.com/i/B-M/130/70264/10002/-1

It's touted as having a "bypass that allows a controlled amount of transmission fluid to bypass the stacked plate core when the fluid is cold. This is beneficial in cold climates to guard against lube system failure. Viscosity controls the transmission fluid and returns it directly to the lube circuit through bypass openings in the stacked plate core. To provide optimal heat transfer and protect against lube system failure, more transmission fluid is directed through the core as the temperature increases."

I also made up a cover plate that slips over the front of the cooler and leave it on all winter.

A couple of suggestions:

Mount the tranny cooler in front of the A/C condenser, nice and close to it so air will be forced to pass through the cooler and not just go around it. Also, when going slow while playing in the rocks and dirt the engine cooling fan will do a better job drawing air through the tranny cooler.

Use "fuel injection" hose clamps to avoid chewing up the hoses like regular hose clamps would do.

https://www.jegs.com/webapp/wcs/stor...rsistYmm=false

2 - I believe that our 4Runners share the same basic suspension components - although my old 2012 Trail Edition has KDSS and a locking rear diff, and your 2019 Limited has A-TRAC, my GVWR and GCWR are the same as yours, i.e. 6,300 and 11,300 lbs respectively. I don't know what your front and rear axle weight ratings are, but mine are 3,000 lbs front and 3,450 lbs rear, and with my 1st Gen (lighter tongue than 2nd Gen) 19' Escape, although I'm comfortably under the front axle weight limit, I'm closer than I would like to the rear axle weight limit. The weights below are from 3 different hitched-up weigh-ins, the first with driver and passenger and full gas tank, second and third with driver only and 1/2 full gas tank, and all with the trailer tanks fresh 1/2 full, grey and black empty.

4Runner Front: 2450 2400 2440 (limit 3000)

4Runner Rear: 3425 3250 3220 (limit 3450)

4Runner Total: 5875 5650 5660 (limit 6300)

Trailer Total: 3550 3500 3560 (limit 4000)

Combined Total: 9425 9150 9220 (limit 11300)

With no trailer: 4Runner Front 2700 and Rear 2600

You can see that the tongue weight takes a fair bit of weight off the 4Runner front axle, and adds a lot to the rear. I would be concerned about the tongue weight of a 2nd Gen 21' on the rear axle. I'm at around 400 lbs on the tongue weight, so I'm well within the 4Runner's 500 lb hitch limit, but don't have much of a cushion on the rear axle.

3 - When towing, I generally use "D" when on level terrain or slight downhills where engine braking isn't needed and I see a slight improvement in instantaneous MPG likely due to the drop in rpm's, but when on even a slight sustained uphill, much less a real climb, have found that using "S" keeps the torque converter locked and the tranny fluid temperature down. The way it works is that you flick the shift lever to the left and it puts it into "S-4", effectively keeping it from going up into 5th. If you then flick it backward one time, you get "S-3", keeping it from shifting up into 4th or 5th. For real steep ups or downs, you can flick it backward again into "S-2" and keep it out of 3rd, 4th, and 5th. You can keep it in "S" and flick it forward a few times all the way back up to "S-5" if you want. I think I mentioned in a previous post that it seems like the pump that circulates the ATF through the tranny cooler is driven by the input (engine) side of the tranny, not by the output (drive shaft) side, so if you keep the engine revs up by using lower gear(s), you get more ATF cooling, plus staying out of 5th keeps the torque converter locked which seems to make an immediate and large reduction in the ATF temp. Kinda funny to base your gear selection on ATF temp, but whatever works...


4 - When I started towing with the 4Runner and saw the large amount of rear suspension sag I knew I needed stronger springs back there. I installed the Timbren bump-stop / helper springs on the rear in part because at the time I was in the midst of having a ruptured disk in my lower back, and wasn't really in the mood to tear the rear springs out to install air bags. I've been really happy with the (overpriced) Timbrens - when I got them they were $164, and they've since gone up to $215 on Amazon. One caveat: Although the ones I got were specified for the 4Runner, when I initially installed them in place of the stock bump stops, it was obvious that the rubber spring was displaced to the rear of the 4Runner's differential, even when slid forward all the way on the slotted mounting holes it wasn't centered over the axle housing by a good 3/4" or so. See the pic. Remarkably, and to their credit, the folks at Timbren took back the originals, and welded me up a set that allowed the spring to be centered over the axle. I don't know if I was the first person to complain or whether they've since addressed the problem or not.


Although air bags are a lot cheaper, I'm glad I didn't have to go to the trouble of installing them inside the coil springs, and I don't miss messing around with inflating/deflating them. The Timbrens just work - with no fussing around. Highly recommended.

Originally Posted by Telescopist

1. On the shift lever transfer case you can move from Drive to S-mode in a blink of the eye. On steep descents where it's important to increase engine breaking force or when ascending increase torque which of the 5 levels in S- mode is advisable? Default is "4" according to the manual.
2. On relatively flat terrain should I stay put in the drive mode?
3. There has been some discussion about installing an auxiliary tranny cooler. Several list members report that a cooler reduces the tranny temperature by between 20 - 30 degrees. Any input on that would be appreciated.
4. For peace of mind would it make sense to monitor the tranny temperature with a Scan Gauge 11 ( like a few members have)? Or is this just another distraction?
5. Is it a valid argument to, as one member recently wrote to: "swap out the hitch and beef up the suspension a bit." What is wrong with the current hitch that it would need to be swapped out? Has anyone beefed up their suspension?
6. Does beefing up the suspension imply that you don't need a WDH?

1-3 See above.


4 - I would absolutely recommend getting a ScanGauge. Without a tranny cooler, I found that even when NOT towing, going up some of the Northwest mountain passes, even in mild ambient temperatures, the ATF temps can start pushing 230 degrees - especially when in "D". I've never gotten my ScanGauge to display temps from both of the A750 tranny sensors (admittedly I haven't tried too hard since I'm quite sure I'm seeing the torque converter temp, judging by how fast it changes when locked / unlocked - the pan temp would be more constant). After monitoring it for a while, you'll get a feeling for when you need to start getting concerned and drop down a gear or two. When I start pushing 225-230 or so, I just pull over when I have a chance, let it fast idle in neutral, and have a cup of coffee.


Our transmissions, the Aisin A750, seem to have a good reputation (even if, ahem, perhaps missing a few ratios) but heat kills things, especially automatic transmissions.


E.g.: Avoiding Common Problems with the Toyota A750F Automatic Transmission


I'm on a 25,000 mile ATF change schedule, and am just about due.



5 - Not sure about swapping out the hitch and beefing up the suspension. The receiver is integrated into a stamped steel crossmember at the rear of the frame, and the crossmember is welded in place. I recall some talk a few years ago on a 4Runner forum about being able to get a Lexis SUV hitch that supposedly bolts to the frame using longitudinal mounting plates that run along the inside edges of the frame rails, but I don't know how you would get the original hitch out of the way to allow the Lexis hitch to fit in there. I asked Toyota about exactly what component(s) in the rear suspension determine the maximum "Gross Axle Weight Rating" - wheel bearings, springs, spring mounts, whatever, and (no surprise) they didn't seem to know what I was talking about. Adding Timbren's or airbags won't increase the axle weight rating. To really "beef up" the suspension, you could swap in a new heavier-duty differential and springs, but that would only mean, so sorry, that you bought the wrong vehicle in the first place...

[Telescopist]

Originally Posted by Great Eggstrications

I'm sort of late to this party - been overseas for the past 6 weeks - but had a PM from Telescopist when I got home a few days ago:

All is forgiven. Better late then never. I might add that you have become the life of the party!

[B][I]I will be picking up my 21 Escape on May 21. I just purchased a 2019 4Runner Limited.

We are picking up ours on the 21st as well. Our orientation is at 8:30 AM. We will be checking in to the Best Western on Sunday. So will CPA Charley. I look forward to meeting you.

1 - I would highly recommend that you install a tranny cooler. The consensus appears to be that a stacked plate type would be better than a tube and fin type - the former has more heat transfer capability for the same size cooler, and things are sort of tight behind the grill.

I installed a B&M 14,400 BTU "SuperCooler" from Jeg's - about 100 bucks currently.

https://www.jegs.com/i/B-M/130/70264/10002/-1

It's touted as having a "bypass that allows a controlled amount of transmission fluid to bypass the stacked plate core when the fluid is cold. This is beneficial in cold climates to guard against lube system failure. Viscosity controls the transmission fluid and returns it directly to the lube circuit through bypass openings in the stacked plate core. To provide optimal heat transfer and protect against lube system failure, more transmission fluid is directed through the core as the temperature increases."

I also made up a cover plate that slips over the front of the cooler and leave it on all winter.

Understood. I was ignorant about the different types of coolers. Now you have painted a clear picture. I was concerned about the transmission exposed to cold temperatures (we live in a northern clime). Now I see that there is a simple solution.

A couple of suggestions:
Mount the tranny cooler in front of the A/C condenser, nice and close to it so air will be forced to pass through the cooler and not just go around it. Also, when going slow while playing in the rocks and dirt the engine cooling fan will do a better job drawing air through the tranny cooler.

Use "fuel injection" hose clamps to avoid chewing up the hoses like regular hose clamps would do.

I'm taking notes.

2 - I believe that our 4Runners share the same basic suspension components - although my old 2012 Trail Edition has KDSS and a locking rear diff, and your 2019 Limited has A-TRAC, my GVWR and GCWR are the same as yours, i.e. 6,300 and 11,300 lbs respectively. I don't know what your front and rear axle weight ratings are, but mine are 3,000 lbs front and 3,450 lbs rear

3. Yes. the 2019 4Runners have a GVWR of 6,300#/Front 3,000#/Rear 3,450#.

The weights below are from 3 different hitched-up weigh-ins, the first with driver and passenger and full gas tank, second and third with driver only and 1/2 full gas tank, and all with the trailer tanks fresh 1/2 full, grey and black empty.

4Runner Front: 2450 2400 2440 (limit 3000)
4Runner Rear: 3425 3250 3220 (limit 3450)
4Runner Total: 5875 5650 5660 (limit 6300)
Trailer Total: 3550 3500 3560 (limit 4000)
Combined Total: 9425 9150 9220 (limit 11300)

Very helpful breakdown. It seems that it is the rear axle where weight limits become something to focus on.

You can see that the tongue weight takes a fair bit of weight off the 4Runner front axle, and adds a lot to the rear. I would be concerned about the tongue weight of a 2nd Gen 21' on the rear axle. I'm at around 400 lbs on the tongue weight, so I'm well within the 4Runner's 500 lb hitch limit, but don't have much of a cushion on the rear axle.

What would you recommend then? An equalizer hitch.Or something (E2) with integrated sway control perhaps?

3. - When towing, I generally use "D" when on level terrain or slight downhills where engine braking isn't needed and I see a slight improvement in instantaneous MPG likely due to the drop in rpm's, but when on even a slight sustained uphill, much less a real climb, have found that using "S" keeps the torque converter locked and the tranny fluid temperature down. The way it works is that you flick the shift lever to the left and it puts it into "S-4", effectively keeping it from going up into 5th. If you then flick it backward one time, you get "S-3", keeping it from shifting up into 4th or 5th. For real steep ups or downs, you can flick it backward again into "S-2" and keep it out of 3rd, 4th, and 5th. You can keep it in "S" and flick it forward a few times all the way back up to "S-5" if you want. I think I mentioned in a previous post that it seems like the pump that circulates the ATF through the tranny cooler is driven by the input (engine) side of the tranny, not by the output (drive shaft) side, so if you keep the engine revs up by using lower gear(s), you get more ATF cooling, plus staying out of 5th keeps the torque converter locked which seems to make an immediate and large reduction in the ATF temp. Kinda funny to base your gear selection on ATF temp, but whatever works...

This is what I needed clarification about. Thanks!

4 - When I started towing with the 4Runner and saw the large amount of rear suspension sag I knew I needed stronger springs back there. I installed the Timbren bump-stop / helper springs on the rear in part because at the time I was in the midst of having a ruptured disk in my lower back, and wasn't really in the mood to tear the rear springs out to install air bags. I've been really happy with the (overpriced) Timbrens - when I got them they were $164, and they've since gone up to $215 on Amazon. One caveat: Although the ones I got were specified for the 4Runner, when I initially installed them in place of the stock bump stops, it was obvious that the rubber spring was displaced to the rear of the 4Runner's differential, even when slid forward all the way on the slotted mounting holes it wasn't centered over the axle housing by a good 3/4" or so. See the pic. Remarkably, and to their credit, the folks at Timbren took back the originals, and welded me up a set that allowed the spring to be centered over the axle. I don't know if I was the first person to complain or whether they've since addressed the problem or not.

I'm on eTrailer's site. I'll make sure to ask

4 - I would absolutely recommend getting a ScanGauge. Without a tranny cooler, I found that even when NOT towing, going up some of the Northwest mountain passes, even in mild ambient temperatures, the ATF temps can start pushing 230 degrees - especially when in "D". I've never gotten my ScanGauge to display temps from both of the A750 tranny sensors (admittedly I haven't tried too hard since I'm quite sure I'm seeing the torque converter temp, judging by how fast it changes when locked / unlocked - the pan temp would be more constant). After monitoring it for a while, you'll get a feeling for when you need to start getting concerned and drop down a gear or two. When I start pushing 225-230 or so, I just pull over when I have a chance, let it fast idle in neutral, and have a cup of coffee.

I've ordered a Scan Gauge.

Our transmissions, the Aisin A750, seem to have a good reputation (even if, ahem, perhaps missing a few ratios) but heat kills things, especially automatic transmissions.

I'm on a 25,000 mile ATF change schedule, and am just about due.

When you change the ATF do you have the shop flush out the old fluid or simply drain and replace? The service manager at my local Toyota dealership told me that a flush and replace is around $300.

I'm nominating you for the '2019 Escape Owners Forum Contribution of the Year'. If such a award doesn't exist then its my treat for beers when we arrive in Chilliwack. Thanks for this information.

[Great Eggstrications]

Oops - I kinda sorta forgot the end of the story - it was late, I was tired, had jet lag, etc, etc.

6 - So... beefing up the rear suspension isn't really going to help with the potential rear axle overload, but if you can use a WDH to transfer some of the load off of the rear axle and move it to the front axle, that would seem to be a good approach to take. Looking around the web, there seems to be some debate about using a WDH on a 5th Gen 4Runner. I would try to get a definitive answer from our friends at Toyota. I tried but never got anywhere with them.

[Telescopist]

Originally Posted by Great Eggstrications

Oops - I kinda sorta forgot the end of the story - it was late, I was tired, had jet lag, etc, etc.

6 - So... beefing up the rear suspension isn't really going to help with the potential rear axle overload, but if you can use a WDH to transfer some of the load off of the rear axle and move it to the front axle, that would seem to be a good approach to take. Looking around the web, there seems to be some debate about using a WDH on a 5th Gen 4Runner. I would try to get a definitive answer from our friends at Toyota. I tried but never got anywhere with them.

Yes. I did call the service department several days ago. They have no clue. If it isn't part of a standard maintenance protocol they either haven't been trained to answer the question, have had no curiosity about the question, claiming ignorance about the question, or some combination thereof.

This was born out by our 'salesman' who didn't even know whether or not the 4 Runner had a tow package. He expressed puzzlement when I asked him where the 4 pin and 7 pin receptacle was located. It's understandable really. He had only been working there 16 years.

[Telescopist]

4 - When I started towing with the 4Runner and saw the large amount of rear suspension sag I knew I needed stronger springs back there. I installed the Timbren bump-stop / helper springs on the rear in part because at the time I was in the midst of having a ruptured disk in my lower back, and wasn't really in the mood to tear the rear springs out to install air bags. I've been really happy with the (overpriced) Timbrens - when I got them they were $164, and they've since gone up to $215 on Amazon. One caveat: Although the ones I got were specified for the 4Runner, when I initially installed them in place of the stock bump stops, it was obvious that the rubber spring was displaced to the rear of the 4Runner's differential, even when slid forward all the way on the slotted mounting holes it wasn't centered over the axle housing by a good 3/4" or so. See the pic. Remarkably, and to their credit, the folks at Timbren took back the originals, and welded me up a set that allowed the spring to be centered over the axle. I don't know if I was the first person to complain or whether they've since addressed the problem or not.

I contact Timbren. The first response was that they didn't have any documentation about the slotted mounting holes not being centered over the axle housing. I followed up with 'but someone on a forum I participate on said they did have a problem and you corrected it.' Whoever I was communicating with said that they would look into it.

Meanwhile, I found this YouTube demo that was done in Sept. 2018 on installing a pair of Timbren rear bumper stops on a 5th Gen 4Runner.

[Brian B-P]

Originally Posted by Great Eggstrications

I think I mentioned in a previous post that it seems like the pump that circulates the ATF through the tranny cooler is driven by the input (engine) side of the tranny, not by the output (drive shaft) side, so if you keep the engine revs up by using lower gear(s), you get more ATF cooling...

Yes, that it normal and conventional automatic transmission design practice. With only one pump, it's really the only choice, since fluid pressure is needed whenever the engine is running, but when the vehicle is stopped only the input shaft is turning, not the output shaft.

This is why people who flat-tow automatic transmission cars behind their motorhomes need to add an electrically-driven fluid pump (or other questionable aftermarket hacks) to keep the towed car's transmission from being destroyed. To allow stop-start engine operation features (in which the engine is automatically stopped when you stop, and automatically re-started when you touch the accelerator to move again), the newest transmissions have an electrically-operated pump as well as the input-shaft-driven pump... but obviously not in the Aisin A7xx.

[goalie39]

I tow a 2010 19' with a 2015 4Runner SR5, and a 2007 4Runner before that.
I tow in S-4 pretty much all the time, as suggested by the manual. Keeps the tranny temp down. Of course on steep descents you'll want to downshift to S-3 or S-2 to use engine braking. On a mild downhill on a straight road I might do S-5, but I find you only need S-5 if you want to go over 65mph.
I use the Android "Torque" application and a bluetooth OBD reader to check the temp, but usually I only look at it on steep climbs. Highest temp I've hit so far is 225 degrees.
I purchased the 4Runner used, and had the tranny fluid replaced and a cooler installed at the same time, so I don't have a comparison for how it runs without the cooler.

I used to tow with the standard hitch and sway bar, but there was a lot of sag and the ride was bumpy -- the porpoising effect. So I installed an Equalizer WDH and love it, so much smoother. The Fastway E2 is similar -- if I bought a new Escape, that's what I'd have them install.