Toyota power steering cooler on my 80 (1 Viewer)

[asutherland]

I've noticed how my power steering is affected by the warm summer temperatures and larger tires. In the winter, with my smaller tires and cooler ambient temps, it behaves way better. I've done a bit of research on here and decided to install a small oil cooler in line with my "paperclip" style oem power steering cooler.

I wanted something small, and something Toyota. I found a 8 x 5 inch Toyota ae86 oil cooler that fit the bill. Cost me $20. Plus now I can drift

It was nearly a perfect fit right out of the box. I had to make a couple small brackets, a couple adjustments of the stock one, and now it fits perfectly and is very steady. The ATF lines will go down under the rad and join in to the low-pressure PS return line. (tomorrows job).

And yes, if you were wondering, that is an FJZ80 oem transmission cooler on my 1HD-T you spotted in one of the pics below.

 

[asutherland]

Sooo it was brought to my attention that the way I oriented the cooler could cause it to trap air in the system. D'oh. I am not a fabricator by nature, so everything takes me extra long to do as I learn. Which is always good (learning), but.... it's very frustrating to have to redo the days work.

Oh well! Such is life. So I got crackin' this afternoon and made myself up 3 new brackets all from scratch. Considering I am a complete fab noob, I don't think they turned out terribly bad.

Bracket one (top) ... even I found this one easy.

Bracket two (bottom) ... This was a bit more complex, but I managed to get it right the first time! And using my vice to bend.

Bracket one and two mounted to the cooler

Bracket three (side) ... By now I was "in the groove" so I didn't even hesitate to make this even more complex one. I wasn't 100% sure on how to make it strong, being longer and flat metal, but I either got it right or just lucked out because it's quite firm once in place. I even added speed holes (ok, would you believe weight reduction? .... no? How about... air holes to allow more air to hit the rad? )

Pre-paint test fit, fits well!

Painted and mounted!

I then went to run the atf hoses, and found I was 10 inches short

oh well, tomorrow's job... finish hose runs, tie into power steering return line, flush and fill with atf.

 

[Iceaxe]

You should think about selling these as a kit!

 

[asutherland]

Being as much of a noob at this that I am, I take that as an extreme compliment! Thank you!

I'd be embarassed to state how much time it did take me though. HOWEVER... a friend of mine has a cnc machine and is always looking for projects. It'd make the fabrication of these brackets a breeze. How many ae86 coolers do you think we could find though... lol

 

[MDarius]

So, I don't know anything about how all this works, but if it's running fine in the winter without the cooler, will the cooler be overkill 4 months of the year? What's the optimal temp range? School me.

 

[SmokingRocks]

That was a concern on my last car and the aftermarket tube and fin cooler I put on the transmission. I fitted a bypass valve to it and it worked wonders.

 

[asutherland]

Disclaimer: I am no expert!

I'll assume the optimum temps for ATF are similar, if not the same, in a PS system as in a transmission system. (let me know if I am wrong with that assumption!)

I believe operating temp of an automatic trans is somewhere around 80 degrees + F. With the FJ80 front mount transmission cooler in line with my "paperclip style" transmission cooler, even in sub -10C temps in the winter, I see 125-150F after 5 minutes of driving and up to 200F on hills.

While I don't have a gauge on the PS system, judging by how hot it WOULD get in the summer (hot enough for the fluid to thin out and cause the pump to stop working properly) I don't have any concerns with it being too cold. I would expect the temps to quickly rise above 80 degrees.

Cool ATF temps are a good thing! Temperature kills transmissions (and causes PS systems to work inefficiently)

 

[MDarius]

Sounds good enough to be true!

 

[SmokingRocks]

Transmissions typically need to be between 110-130 degrees before shifting properly and can run up to 210 even short durations to 220 without problem. They should be running in the 150 - 175 range flat land cruising with no trailer.

 

[Cruzerman]

Looks great! What issue were you having? How large of tires? I ask because you don't seem to live in a "hot" climate. I know many people running trails with me on tires up to 36", using the stock setup, and I don't recall anyone having heat issues with the steering. I'd be wondering if you're having some other issue. No matter what, I like the cooler. I just would be concerned that there is another issue here.

 

[Teddy]

Looks great! What issue were you having? How large of tires? I ask because you don't seem to live in a "hot" climate. I know many people running trails with me on tires up to 36", using the stock setup, and I don't recall anyone having heat issues with the steering. I'd be wondering if you're having some other issue. No matter what, I like the cooler. I just would be concerned that there is another issue here.

I was having overheating issues with mine a few years ago on the trails in the southeast and actually blew up a power steering pump last summer at Windrock because it got so hot. Issues were usually on 90+ degree days with 35's going slow in rocks. Prior to that I boiled the fluid several times. Myself and two well known LC mechanics on this forum went through the system and could find nothing wrong, other than the system not being able to handle the extra load. I thought for a while the screen in the reservoir was clogged or something, not allowing fluid to circulate, but that wasn't the case.

Maybe it's just my driving style, IDK. Either way, I ended up replacing the factory cooler with the finned Mr. Gasket unit that several guys here use and replaced all my factory hard lines with soft lines routed in a more direct path. Since then I haven't had anymore issues with the extra fluid and extra surface area to dissipate heat.

 

[Cruzerman]

I do understand that you can overheat the power steering system on these rigs and that the stock "cooler" is anything but ideal. However, it appears that op lives in BC, which isn't exactly a hot location. And he also says "In the winter, with my smaller tires and cooler ambient temps, it behaves way better.", which makes me think that even in winter, it still has some issue (just much less). This just has me wondering if there is something else going on.

 

[SmokingRocks]

I like your idea. After some long hot days at cruise moab last year I felt that my power steering was not working as well as it usually does. Heat very well may have been the issue. I think I will look into add your mod to my truck thanks.

The best thing an 80 series owner can do to increase the longevity of their rigs mechanical components is to effectively manage heat. I would also highly suggest adding an 8" pusher fan to the transmission cooler. I haven't installed a temp gauge yet but I know that after 4-5 hours in low range on the trail my transmission is hot hot and shifts poorly. It's been like butter ever since I added the fan.

 

[MDarius]

Summers in Kamloops are actually pretty hot. Not Arizona hot, but Utah hot, maybe a little shorter. My PS complains in the summer. I just assumed I had a worn out pump, could be temps... AND a worn out pump...

 

[asutherland]

The OP here does live in a fairly hot climate in the summer. Usual summer temps are 32 C (which is 90F) for weeks, last summer we reached 40C. (104 F) for a few days. It was actually 42C in Lillooet the summer before, I was out hiking (boy that was dumb).

In the winters, we see - 20C for a few weeks, average temps are just below zero. Though this winter was mild.

I also thought there may be something wrong with the system, so I flushed it a couple years ago and also completely rebuilt the pump too. The whining stopped, but the overheating continued.

Question for you USA guys, when you say oem power steering cooler, are you talking about the two hardlines that cross along the front frame, one from pump to box and then box back to res? That's all I have for "cooling" on my hdj81.

No problems with overheating in the winter. Winter tires are 33 inch winter radials, summers are 35 inch MT

 

[asutherland]

Smoking rocks, trans temp gauge is a great idea. I monitor mine like a hawk, even more than my EGTs. When you're doing Forest service roads and light wheeling, do you put it in low range? Having it in low range for long hills "offroad" helps with the trans temp dramatically.

Thanks for the feedback to all. I did the fluid exchange last night, with the new cooler mounted. Everything appears to be working fine. (it was a pita, messy job, the hardline ends were difficult to get at...)

I'll report back here if anything noticeable happens, or if a good period of this summer goes by without having the familiar issue.

 

[Output Shaft]

PS fluid should be at least 176° F for optimum pump performance.

Shoot a IR temperature gun at the PS reservoir or dip a thermometer in the fluid to verify temps.

That cooler was designed for a transmission, not a PS pump.

Read the power steering testing instructions in the FSM. Temperature guidelines are noted.

 

[asutherland]

Thanks, I did read the manual, and saw that it stated to bring the temperature up to 176 before performing the tests. Good idea on the IR gun.

I am aware that's not a PS cooler. My truck was also not intended (by toyota) to be lifted with armour and have 35 inch tires either. Sometimes factory is not sufficient.

Like, for example, the fact the HDJ81 does not come with a front mount transmission cooler, only a "through the rad" type. It is incredibly inefficient for cooling the trans especially when fitted with large tires in a hot climate driving up BC mountain passes.

 

[alia176]

Disclaimer: I am no expert!



I believe operating temp of an automatic trans is somewhere around 80 degrees + F. With the FJ80 front mount transmission cooler in line with my "paperclip style" transmission cooler, even in sub -10C temps in the winter, I see 125-150F after 5 minutes of driving and up to 200F on hills.

The paperclip cooler is for the PS cooler, not the Transmission cooler.

Good job on the install!

 

[asutherland]

Thanks! Do the USA 80 series have an actual paperclip shaped cooler for PS? Mine does not, it only has two hardlines (one for feed and one for rerurn) that run side by side along the front cross member.

I know, we were kind of talking about a couple things. Transmission wise, the hdj81 doesn't have a front mount trans cooler. It only has the one that passes through the bottom of the radiator. I added one from a fj80 I bought second hand. It made a substantial difference in transmission temps.