Transmission Cooler Install

[bornreadyk5]

Whats your opinion on installing a aftermarket external tranny cooler?

Hook it up alone/seperate from Radiator cooler? or

Hook it up in conjunction with the factory radiator cooler?

Gracias.

 

[jekbrown]

Whats your opinion on installing a aftermarket external tranny cooler?

I think its a good idea.

Hook it up alone/seperate from Radiator cooler? or

Hook it up in conjunction with the factory radiator cooler?

if you live somewhere where it gets really cold (sub zero!) then run it through the radiator... if you don't, just run it through the cooler only. If its a really cold day, just let the rig warm up for a min before driving, you'll be fine.

j

 

[89GMCSuburban]

I was told, run it through the aftermarket first, then the radiator one. That way on cold days, the fluid will get to a good temp after passing through the rad cooler.

 

[Leper]

I was told, run it through the aftermarket first, then the radiator one. That way on cold days, the fluid will get to a good temp after passing through the rad cooler.

But that will have a negative effect on hot days. IMO run through the radiator then the A/M cooler. If you have to deal with extreme cold for a little while, put some cardboard in front of it.

 

[neverendingproject]

I say run it through the cooler alone. Most coolant temps get higher than the recommended 165* that the tranny should run. IIRC there is a 10000 mile decrease in wear for every 10* the tranny temp goes down.

 

[78Suburban]

I've done much searching on ck5, and have found that there is alot of debate about which cooler to run first, the radiator, or the aftermarket..... people say that running it to the radiator cooler first will keep the temps down low. Other people say to run it to the aftermarket cooler first, to avoid overcooling, thus not evaporating the moisture out of the ATF, thus causeing rust......
Bottom line,
I don't know
James

 

[sweetk30]

get the temp switch unit . then it will flow threw rad till heat trips it to flow threw the extra cooler. summit # prm-1070 and prm-1060 both good units.

 

[k20]

if your south of the mason-dixon, I'd just run it through the aftermarket cooler(what I did), if above that, I would run it through the radiator and then the cooler. Reason being, through the radiator, itll get to 210, then after the cooler, itll be 160ish, if you ran it the other way, itd be 160ish, and then go up to 210, kinda counterproductive if you ask me. (I just pulled these #'s out of a hat so dont start lol).

 

[xtrmjoe]

I would not run it thru the radiatior at all. If you ever overheat the eng, you will also overheat your transfluid. Overheating the trans fluid is the 1# reason most auto trannys fail. If you are really that worried about having the fluid stay to cold you still have 3 options any or all of them will solve the problem: 1) Run sythetic fluid 2) Get a inline termosat 3) Cover the cooler when in extreme cold temps.

I have dual coolers and dual filters with a inline thermostat and have been very happy the the temps I have run in all conditions from Tahoe snow, Wyoming road trips and the cali sun.

 

[sandawgk5]

I am running mine through the radiator then through the aftermarket cooler. I got a Long's Tru-cool Max 40,000 gvrw with the thermal switch.

Ira

 

[ntsqd]

If you run it thru the A/M cooler first you can reject the most heat. Then run it thru the rad if you live in cold country. Running the trans too cold can be as bad as too hot. The rad acts like a crude t-stat for the trans. making sure that it always warms up at the speed that the engine warms up. The worst running it thru the rad after the A/M cooler can do is run the trans at engine temp, and it's not likely to get completely to the engine's temp b/c of inefficiencies in thermal transfer.

Alternatively you could use one of these oil t-stats.

Being on the left coast I could probably run the A/M cooler alone, but I know that I'll occasionally take the Sub into snow country so I ran it thru the radiator after the a/m cooler.

 

[jekbrown]

maybe a dumb question, but wouldn't warming a rig up for a few minutes accomplish the same thing as having the trans fluid run through the rad? I mean, if a rig has been sitting a couple of days, the rad fluid is similar in temp to the outside air... right? If thats the case, it doesn't seem like its going to warm up the tranny fluid at start up... its gonna take a little while. At the same time, doesn't the tranny warm its own fluid as it pumps it around? Seems even if you were in snow country you could just start 'er up and let her idle for 5 mins and be on your way.

j

 

[dubbyx]

I've never heard of anyone complaining about their tranny fluid being too cold, and as far as I can see the only time it would be a problem is in extremely cold climates, or if the fluid never got hot enough to repel the condensation in the system...

Either way, I ran my cooler in front of the radiator and let it stand alone. I havn't had to worry about "warming up" my tranny... by the time my engine's warm enough to run right everything else has been ready to go for 5 minutes...

 

[76zimmer]

I hooked up a 18000gvw cooler when my 85 700R4 was new, and ran through the rad. and to the cooler, then back to the trans. I got 240,000 out of it, although not towed with a lot. Used drive only when I did tow. I live in Michigan, and never had any problems with driveability from -20 to 100.

 

[hack500]

one problem with through the radiator is if the internal seam leaks anti-freeze/water into your ATF. it'll look like pepto-bismol and can destroy your tranny, too.

 

[dubbyx]

Another thing I learned the hard way on radiator/tranny coolers--always flush them out good before installing. I put a new radiator on my 1-ton a couple years back and just hooked it back up to the tranny lines. About 3 days later my tranny started acting up on me, and the tranny filter had filled with shavings from where the fittings were drilled out.

Prolly woulda been fine if my filter was new, but seeing as how it had been on there quite some time it didn't take much to fill it up to the point of blocking off the flow.

 

[78Suburban]

So do tranny coolers come with fitting that directly screw into where the lines enter the radiator? If so, which coolers come with t-fittings that work with our stock lines?
thanks,
James

 

[mouse]

So do tranny coolers come with fitting that directly screw into where the lines enter the radiator? thanks,
James

Yes, every one I have bought come with the adapters.

No, you don't want a "T" setup. The cooler should be one path.

 

[ntsqd]

But that will have a negative effect on hot days. IMO run through the radiator then the A/M cooler. If you have to deal with extreme cold for a little while, put some cardboard in front of it.

Yes and no. It will heat up the fluid, BUT it will also act as a thermo-stat & keep the fluid from being excessively chilled. You want the fluid hot enough to boil out any moisture. The commonly quoted temp around this bbs is 165*f, but I'm not convinced that is warm enough. I think more like 170*-175*f is needed.
And if you're running a normal t-stat then the ATF will only, at the most, be that temp. Which is well within the acceptable range for ATF. But remember that the t-stat sets the engine hot exit temps and the OE cooler is in the cooled rad tank, which is well below the t-stat temp.

maybe a dumb question, but wouldn't warming a rig up for a few minutes accomplish the same thing as having the trans fluid run through the rad?
j

Not really, no load on the trans. One of the things that the rad cooler does is act as a trans heater on cold start-up. So on a cold start-up it's actually putting some heat into the fluid to warm the trans up more quickly.

 

[1987Blazer]

I just hooked up my cooler last weekend. I goes through the radiator then the cooler. I'm glad the poll is in favor of hooking it up that way