Question : Optimum Trans fluid temp?

[3400-95-Modified]

Ok well I have a high stall converter in my car and well yeah it generates a little heat. I noticed with the stock cooling system the trans temp would climb quickly and I think it would easily reach over 200* F not sure how high since the one time I was logging it I saw 205 and then I went out and bought a Hayden pipe/fin cooler... not sure the exact size but it had 3 U's on one side. Well Saturday I was out driving and I noticed the temp again was up around 200, like 202 max, so I know temps like that arent that good but at the same time arent the end of the world... so I grabbed a Maxi-Kool XL cooler, supposed to be 33% more efficent than a pipe fin style.

BUT my real question is at what trans temp should I really start to worry? is 200* bad for it? or is that around norm?

[1988GTU]

That is about normal. I installed a trans cooler (with gauge) into my buddies 3.4 gtp and the temps are sitting at about 185-199 and that is for a rebuilt stock trans with a slightly higher stall converter.

[X11_STE]

I've got an HD van that does some serious hauling and the trans stays around 180-200. Idd I was you, I wouldnt worry about it. Now, when tranny fluid reachs 420 degrees, it'll only last 20 mins before being trash.

[3400-95-Modified]

420*!!!! HOLY HELL... I think the 300 mark would be way pushing it...on the back of my cooler it says, 315* "seals and clutches burn out, carbon forms" 800miles max... LOL

for 195*f it just says approx 50,000 miles of use or so...

and 175* 100,000 miles of use... I'm sure thats a little exaggerated but I wouldn't mind seeing 180* constant, rather than 205*

The new style cooler I got looks like a mini coolant radiator, it has two tubes down each side which are connected with runners that have normal type fins between them, there is a total of 30 runners, so I'm sure this cooler should work a bit better than the tube fin style one.

Pics do better talking... this is the one i got.

[1988GTU]

Is that a 8" by 9" with a 1.5" core? You could possibly put a little cooling fan in front of it to cool it more. Just wire it to spin on when XXX*F is reached.

[3400-95-Modified]

11 3/8 x 11 with a 3/4" core

Largest one of that type... the smaller one is 7 1/2 x 11 with a 3/4" core.

[loner666]

I'm putting in an extra fan on top of my cooler and possible another cooler to keep mine down..not sure the exactly temp in F but Ive been seeing around 80-85C so I don't. Seem to be alot happier then my last one was so far

[3400-95-Modified]

edit your gauge to display F

85 is only 185 tho

Its my damn converter that generates so much heat slipping as much as it does.

[IsaacHayes]

low stall FTW just ribbing ya

I'll scan mine sometime now that it's hot and humid outside and see where it's at. I don't have headers or high stall so it's going to read what a "stock" trans should... I have seen around 200 though before IIRC. It's always hotter than the motor is from what I remember.

Hmm, my trans has like 215,000 on it, so it must be running at 130F then huh? LOL :P

[3400-95-Modified]

1650 stall with this cam would probably suck and bog badly... Maybe a 2300 wouldnt be bad though... we'll see after I get some numbers.

[PCGUY112887]

I have the mini radiator type of cooler as well, big one made for RV's and shit.

My temps are around 170-180 with a stock converter and higher tranny pressure.

[pocket-rocket]

I had one on my 91 for a long while before I put a 284 in it. The trans that was in the car at that point had 99k miles on it, which in a Z34 is a wonder how it was still going. At any rate, with that cooler I got 30k miles of hard driving out of it, so I was happy with my investment.

[3400-95-Modified]

I got it installed last night but I didnt scan it when I was joyriding after the 3500 upper swap... I'll check it on my way up to epping on the highway... I cant see how it wont make a difference, it was almost twice the height of the old one, and it's not just 6 straight lines of a pipe going through fins...

[pocket-rocket]

Well IIRC the one you and I have is rated for something stupid like a 16k lbs truck.

[3400-95-Modified]

yeah like 10,000 lbs towing too I think...LOL

Up to Class "A" Motorhomes, Towing up to 10,000 lbs

I would hope this cooler helps...