Tranny Cooler Upgrade Planning

[hdj105]

Also PWR make a twin cooler kit, it’s pricey and I’m searching for pics, but the details are here:

PWR PWO109365K Extreme Transmission Oil Cooler Kit (Toyota Landcruiser 200 Series V8 Diesel 2008+)

PWR PWO109365K Extreme Transmission Oil Cooler Kit (Toyota Landcruiser 200 Series V8 Diesel 2008+)

shop.pwr.com.au

Of course if the transmission was designed properly the torque converter would be locked much earlier, eliminating the heating issues which are common here on the VDJ’s when towing.

 

[linuxgod]

Also PWR make a twin cooler kit, it’s pricey and I’m searching for pics, but the details are here:

PWR PWO109365K Extreme Transmission Oil Cooler Kit (Toyota Landcruiser 200 Series V8 Diesel 2008+)

PWR PWO109365K Extreme Transmission Oil Cooler Kit (Toyota Landcruiser 200 Series V8 Diesel 2008+)

shop.pwr.com.au

Of course if the transmission was designed properly the torque converter would be locked much earlier, eliminating the heating issues which are common here on the VDJ’s when towing.

I'd have to find it again but there is an aftermarket kit in Australia which includes a firmware change for the transmission that can change the lockup, shift points, and some other stuff, and can be configured differently between ECO and PWR settings. No idea if it works with the US models.

 

[TeCKis300]

Also PWR make a twin cooler kit, it’s pricey and I’m searching for pics, but the details are here:

PWR PWO109365K Extreme Transmission Oil Cooler Kit (Toyota Landcruiser 200 Series V8 Diesel 2008+)

PWR PWO109365K Extreme Transmission Oil Cooler Kit (Toyota Landcruiser 200 Series V8 Diesel 2008+)

shop.pwr.com.au

Of course if the transmission was designed properly the torque converter would be locked much earlier, eliminating the heating issues which are common here on the VDJ’s when towing.

That's a good point. The threshold that I hit at 266°F engages the more aggressive factory lockup logic where it locks in 3rd gear and even into 2nd gear. From the dashboard, I can see that it immediately lowers the temps at the torque converter by 30°F, then tracking closer to the pan temps. However at my weight level, pan temps still continue to creep and with a long enough hill, will still get into higher temps. I've seen the pan temps get into 240°F+ on medium grades so lockup will only go so far.

It's arguable whether the factory logic is improper. I'd say that it's good. Automatics have more effective gear ratios than just the gears as the system uses the torque converter outside of lockup as additional dynamic gearing. It's why it unlocks when hitting mild grades to provide the engine just a bit more gearing. Then it'll downshift when it really needs more gearing. It also smooths out transitions. To your point, lockup does reduce heat and may eek a bit more MPG, but it's all a trade and I think the factory programming does walk a reasonable balance.

 

[hdj105]

To your point, lockup does reduce heat and may eek a bit more MPG, but it's all a trade and I think the factory programming does walk a reasonable balance.

I’ve not yet used my URJ enough, let alone when towing, to comment on the trans behaviour to be honest, however there are plenty of local companies offering torque converter lockup kits and remaps for the VDJ200’s (Richard’s, Wholesale Automatics, etc) as trans temps and “loose converters” (heat generators) are a known weakness. No doubt drivers who think lugging in a higher gear rather than downshifting don’t help.

As a side note (and to add substance to my programming comment), there is another local company who have just started offering ZF 8HP70 - 8 speed auto conversion kits for the VDJ7* series. One of their initial prototype VDJ79 dual cab pick ups running a very tuned engine and 37” tyres could only manage to generate 51 degC trans temp when playing hard in the sand on a beach, due to the fact the TC locks after take off in first gear by design. This made them redesign their trans cooler system to include a thermostat.

www.8speed.au (no affiliation, just interested in what they have achieved!)

 

[LX Cruiser]

Just saw this thread. Subbed.

I put a GCS Hayden kit on my '21 Tundra. It works great, and the process is simple enough. Interested to see what people come up with for stateside 200s.

 

[TeCKis300]

Doing this. Expecting 110*F+ temps during the next road trip.

 

[TeCKis300]

Aux aux cooler is in. Decided to augment the stock cooler with another sequentially mounted cooler. Fit great and the plumbing worked out nicely.

Still need to bleed the system and put it to a real test before I vouch for this setup.

 

[linuxgod]

Anxiously waiting to see the results

 

[Five70]

@TeCKis300 any updates? How is this working out?

 

[TeCKis300]

@TeCKis300 any updates? How is this working out?

I split the threads between a planning thread and install/results. I'll add a link to the first thread but results are in this post.

Results​

On average, I'm seeing 5-20°F degree temp drops compared to previous towing temps.

It's hard to nail down exactly as there's so many variables like weather, route, and grade. I don't have a good sense of non-laden temps as I'm only usually monitoring when towing. This particular trip was in early summer with temps in the 90s.

Towing on the level, pan and torque converter temps hover in the 190s. Not that much lower and maybe about 5 degrees lower at cruise versus prior.

View attachment 3380704

Torque converter temps are pretty dynamic, but there is definitely a bigger difference in pan temps staying lower and be able to sink heat in passing and grades with less or slower rise. Faster fall. Previously, when downshifting to 2nd in steep grades for engine braking, I could reliably see torque converter temps spike right to 230°F. Now I'm seeing that in the 210°F.

One of the main reasons for more trans cooling was for brutal long grades where I could reliability trip the torque converter lockup logic at 266°F torque converter temp and 203°F engine coolant. Once tripped, the transmission will aggressively lockup 4th, 3rd, and even 2nd gear. This greatly reduces heat produced in the torque converter at which point it tracks close to pan temps. Problem is the pan temps will continue to climb and I can get it over 250°F at which point I let up hovering around 4k engine RPM, giving into some mechanical sympathy. I've never tripped the 302°F threshold and credit to the robust OEM cooling as moving 15k+ lbs on 35s is some work.

View attachment 3380728

With the additional cooler, I can still trip the lockup logic if I'm super aggressive with basically the gas to the floor and engine screaming near redline for 5-10 minutes at a time. Notice the computed HP and TQ at 413hp and 390 lb-ft (OBD a bit optimistic)...it's basically engine output that drives heat in the transmission and I'm flogging it at max output. I was sure I could trip the lockup logic as I've been able to do that even when it's 40°F in winter. So I was pretty sure no amount of extra aux tranny cooling can prevent that.

Where it earns its keep is that pan temps do seem moderated staying pulled down more. It doesn't feel like it will continue to march into higher temps even when caning it for extended periods. I did just touch 240°F and ran out of hill (Grapevine CA). Still would like to test it in the Sierra's in later summer, but it already feels more resilient.

View attachment 3380729

 

[Boston Mangler]

I split the threads between a planning thread and install/results. I'll add a link to the first thread but results are in this post.

Your attention to detail and explanation is awesome sir!

 

[MTKID]

I split the threads between a planning thread and install/results. I'll add a link to the first thread but results are in this post.

So… it looks like you’ll need a lighter trailer when you get onto 37’s

 

[skrypj]

So… it looks like you’ll need a lighter trailer when you get onto 37’s

Moar coolers.

 

[TeCKis300]

So… it looks like you’ll need a lighter trailer when you get onto 37’s

Does not compute. Moar everything!

Refinishing some 18" wheels at the moment. Might be into 37s by the end of summer? Scratching my head as to how to chop up the LCAs. Tried to press out the bushings and I don't have the right fixture to do it.

 

[2014 LEX 570 GA]

Refinishing some 18" wheels at the moment.

Do tell.

I am onto some Tundra TRD 18s.

 

[TeCKis300]

Do tell.

I am onto some Tundra TRD 18s.

Nothing really special. I have a common Tundra set that I'm painting satin black to get rid of the polished contrast. Installing some fast deflators for large volume 37x12.5s. And I hope to clone aftermarket TPMS as I'll keep a set of 35s for towing work.

Since I have it handy to scale, these Tundra 18x8 +60 OEM wheels are 30.5lbs.

I strongly believe any of OEM wheels are going to be stronger than most aftermarket stuff that are commodity these days.

There's an inordinate amount of attention to unsprung weight on these forums. IMO, for a truck, it's not the major factor people are placing in it. Things like overall diameter and tire parameters play much more into performance, MPG, and ride quality. That's unless it's Baja running pedal to the metal type driving, more akin to a sports car, where unsprung mass and rotational inertia plays a much larger role in acceleration and traction.

View attachment 3645902

Sorry for the ugly wheel, putting my minions to work taking off Plastidip from the previous owners. Hoping to refinish in a satin black like this.
View attachment 3645916
View attachment 3645914

There's enough meat on this topic of Apex Deflators that it deserves its own thread.

Screw on RCV (Rapid Connect Valve)
View attachment 3656748

Install / Replace valve stem RPV (Rapid Precision Valve) in std length (which should work with most OEM wheels)
View attachment 3656749

From the following discussion

 

[NoClue]

I'm running a hayden 679 with a fan. Was flogging her pretty hard in the silver lake sand dunes and she didn't go over 190F

 

[linuxgod]

I'm running a hayden 679 with a fan. Was flogging her pretty hard in the silver lake sand dunes and she didn't go over 190F

Nice. Is yours set up before or after the one in the bottom of the radiator?

 

[skrypj]

does anyone know if the electric fan turns on due to transmission temperatures? I could access the electric fan settings in my previous Jeep Liberty CRD and F150 via tuning software, and both would turn the electric fan(s) if the transmission got too hot. The Jeep was setup like the 200 with a Mechanical main fan and an electric assist

Makes me wonder if putting the second air cooler behind the fan so that it gets active flow at lower speeds too would be a good idea since the stock air cooler is passive airflow.

 

[TeCKis300]

does anyone know if the electric fan turns on due to transmission temperatures? I could access the electric fan settings in my previous Jeep Liberty CRD and F150 via tuning software, and both would turn the electric fan(s) if the transmission got too hot. The Jeep was setup like the 200 with a Mechanical main fan and an electric assist

Makes me wonder if putting the second air cooler behind the fan so that it gets active flow at lower speeds too would be a good idea since the stock air cooler is passive airflow.

Good question and I'm not sure. If it's like the 100-series, the electric fan is primarily for the AC condenser.

I put my tranny aux aux cooler inline with the main mechanical fan for the active airflow. To help slow crawling and sand work.