Automatic transmission cooler

[_RaT_]

I replaced my transmission. They recoomed not using the old cooler for fear of contamination. If I buy an after market oil cooler that is much larger then the stock one my Ford F250 came with, do you still use the radiator cooling portion as well? Would it not also be suspect of being contaminated? Thanks, Rat

 

[Bird]

Rat, lots of RVers have added aftermarket coolers and every one I've ever seen still used the radiator cooler, also. The only question I've seen debated is whether to route it through the radiator, then the other cooler, and back to the transmission or whether to route it through the auxilliary cooler first, then the radiator and back to the transmission. /forums/images/graemlins/laugh.gif

 

[Boomerang1]

You can purchase a flush kit at the local auto parts store that will flush out the radiator. You need both coolers if you want your transmission to live a long and healthy life.

 

[texbaylea]

Bird
I run mine through the auxillary cooler first (which is oversized) then through the radiator cooler to minimize the amount of heat dumped into the engine. Just my logic anyway.

Vernon

 

[Bird]

Vernon, I think (can't say for sure) that the general concensus in the RV magazines was that if you live in a hot climate, you sent it through the auxilliary cooler first to dump a little heat, but if you live in a colder climate, you go through the radiator first to warm the transmission fluid quicker on cold starts. It's been a few years, but I, personally, installed the one on a '70 Olds and a '72 Chrysler that I pulled a travel trailer with and I went the same way you did.

 

[BobRip]

Talking to my local transmission guy, he said go through the radiator first, then the cooler. If you go through the radiator last, you can actaully pickup heat if the enginer is running hot and really have little advantage from the cooler. The transmission needs to run at less than 175 deg F. If the radiator is at 220, then the transmission may get way to hot.

I once put a large cooler in my 86 Caprice and the tranmission shifted very rough at below 32 F. I was told to just use the cooler and bypass the radiator. It works fine now.

Bob Rip

 

[kenmac]

I would run the lines back the way the factory had it .The trans. shop should have flushed out the radiator part that the trans. lines run through when they put it back in. Did they leave this part discnnected?

 

[JerryG]

Get one that is thermostatically controlled.

 

[Bird]

</font><font color="blue" class="small">( run the lines back the way the factory had it )</font>

In my opinion, that's the best advice.

 

[HGM]

I'll agree with the factory setup as well. The trans was guaranteed to run 3yr 36k with that setup. Especially with a larger cooler, you'll be helping either way. I dont really agree with the 175deg statement. Trans fluid is more stable than that, I dont recall a specific number but the heat comes from the TQ converter slipping, not the radiator. The heavier the load, the more the converter will slip to produce TQ, this creates the heat. A cooler helps to disapate that heat.

I would also recomend, hopefully they already know, that the shop flushes the core backwards. This will release more of the build up from it. You could also install a filter, just make sure it has a bypass. This way if the filter cloggs, you dont starve the trans of lube.