Supra Forums banner

1 - 11 of 11 Posts

·
488ci V10 Power
Joined
·
1,785 Posts
Discussion Starter #1
I'd like to know from the tranny experts at what temperature of the transmission does it start to cause damage to parts. Im sure some trannys are different then others so im hoping someone that knows the turbo 400 can respond.

I was out cruising this weekend and after only 40 minutes or so and not getting on it that much my temps were stable at 82c (176 degrees). To me that seems kinda hot, and i want to be prepared or make changes before the 80+ degree heat comes. (it was mid-lower 70's out)

Thanks!
 

·
Bad Karma Supra
Joined
·
2,784 Posts
Mike -

While that is a bit warm...176deg is not going to damage your setup. My question for you is - what type of driving...you say cruising. If you were on fairly open road for 40min - your temps really should've been in the 160deg range. Again, that is depending on your stall speed of course.

On open road, even in Summer, I see ~160F temps on my setup, however, stop and go will bump that to 175 or even with fans on both coolers (both in direct path of air too).

If those temps were on open road...eh, I'd be a bit concerned.

Jay
 

·
488ci V10 Power
Joined
·
1,785 Posts
Discussion Starter #3
Philly Single said:
Mike -

While that is a bit warm...176deg is not going to damage your setup. My question for you is - what type of driving...you say cruising. If you were on fairly open road for 40min - your temps really should've been in the 160deg range. Again, that is depending on your stall speed of course.

On open road, even in Summer, I see ~160F temps on my setup, however, stop and go will bump that to 175 or even with fans on both coolers (both in direct path of air too).

If those temps were on open road...eh, I'd be a bit concerned.

Jay

Thanks jay!

Both my coolers are right in the air path and one of the coolers has a fan. The driving was very minimal stop and go and most 50+ mph for ~40 minutes. I do have a 5500 stall :) so im sure that is affecting it greatly. I was getting on it in boost quite a bit throughout the time since im breaking the motor in now. The previous day of just cruising and not getting into boost that much i drive over 1hr and temps never went above 72c (about 15 degrees) less.

Maybe i should get a 2nd fan on the other cooler to help out. I dont have a lockup anymore so im testing all this out now.

Thanks.
 

·
Bad Karma Supra
Joined
·
2,784 Posts
No problem :) 5500...ready to Git R Dun this year eh!? :D

Stop & Go for ~40min will get you some temps like that, don't be too concerned - I saw temps like that in the Summer, etc on several occassions in stop n go NJ traffic! We just had my tranny apart the other week...guess what? MINT inside - don't stress over 176def :)

Might as well throw on another fan, pretty low $$ to do and easy. I've found it's best to have the fans fire right up as soon as I start driving (open highway aside)...seems easier to keep the temps cool, rather than try to bring them down, once hot.

Heh...maybe I'll mist methanol on the cooler to pull out the heat...ha..

Jay
 

·
Mid-life Realization!
Joined
·
2,530 Posts
Philly Single said:
I've found it's best to have the fans fire right up as soon as I start driving (open highway aside)...seems easier to keep the temps cool, rather than try to bring them down, once hot.


Jay
I agree with Jay. As far as temps, from what I have been able to read/research, the operating temps of most transmissions are similar regardless if a TH400 or other. Your current temps might be slightly warmer due to your radical stall, but still at a temp. that would not cause any heat related damage. As long as you keep your average temps under 200F and change your fluid regularly, the impact of heat related damage should not be significant to the tranny itself.

On the other hand, one source I found a while back said if your average temp is 325F, the time to failure was less than 500 miles :eek2:

Brad
 

·
Shawn Davis
Joined
·
1,662 Posts
I've always understood that 180 and under and you're golden. Above 180 and things degrade pretty rapidly. I think 220 was the number I heard for fairly quick failure. This is all word of mouth.
 

·
488ci V10 Power
Joined
·
1,785 Posts
Discussion Starter #7
THANKS everyone. You guys answered most of my questions! I'll throw on another fan and continue to monitor the temps.

This year i WILL git r dun for sure :)
 

·
Registered
Joined
·
1,421 Posts
Could you possibly add a deeper pan? On a side note, it's good to hear you have your car back together. I assume you'll be hitting Byron soon before it gets too hot? -Nick
 

·
488ci V10 Power
Joined
·
1,785 Posts
Discussion Starter #9
Ex5.0 said:
Could you possibly add a deeper pan? On a side note, it's good to hear you have your car back together. I assume you'll be hitting Byron soon before it gets too hot? -Nick

It has a VERY deep pan already. I guess i have to make some sacrafises with the car.
I WILL be hitting byron very soon, hopefully make some runs before i get booted. :)
 

·
Registered
Joined
·
1,440 Posts
MK4LIFE said:
It has a VERY deep pan already. I guess i have to make some sacrafises with the car.
They make pans that provide cooling as well. There is one in particular that has cooling tubes along the bottom. Where is the filter on your setup? Possibly replace it with one of the inline "Fram" type filters for additional fluid reserve.

For suggestions, in addition to the 2nd fan, that's all I've got for now. :p

John H
 

·
Super Moderator
Joined
·
10,496 Posts
Ubermensch said:
I've always understood that 180 and under and you're golden. Above 180 and things degrade pretty rapidly. I think 220 was the number I heard for fairly quick failure. This is all word of mouth.
Mike

FWIW, my friend, I get 179.6 F when I convert 82 C to Fahrenheit (1.8 x 82 + 32). Just thought I'd let you know since heat sensitivity is an issue.

Like others, I am really happy you have her back on the road again. You know that car inspired me. Good luck with everything.

Ken.
 
1 - 11 of 11 Posts
Top