upgrade transmission cooler

[bbaker2001]

question on upgrading trans cooler.
my 2009 gmc 1/2 5.3 has tow package and have made a few 2500 mile trips. tranny temp does go up. if i want to change or add another, who can tell me the best or biggest i can put on
49000 miles.
i had the fluid changed 300 mile ago

[Tystevens]

225* under duress for a short period of time is not high. If it shows 225* driving down a flat road not towing, maybe you have a problem. If it slowly increases during a climb when towing, and comes back down fairly quickly once the climb is over, your system is operating as intended.

My '10 has 100k miles on it, runs perfectly, and the transmission is in great shape. We hit 225* on many trips, towing in Utah mountains.

[bbaker2001]

thanks I will keep an eye on it. I really don't want to burn up the tranny

[_tpc_]

That temp is fairly high. But if its just a short period, and it usually runs much lower, I wouldn't be concerned.

I start to get nervous when mine hits 205, but I have a 2007 with a lot of miles on it. Usually when it starts to get up there I notice engine temp up as well, and I think thats what makes me nervous.

Now that you know you have the oem one up front (this is the one I added to mine), you could look around on the web for DIY info on replacing it with something bigger. I think the biggest challenge of the job would be getting the fascia off so you could remove the old one and mount the new one. Its a pretty simple job and if you did it yourself, you could probably do it for less than $100.

[bbaker2001]

thanks just saved myself 325.00

[time2roll]

224 is fine. Slow a bit and downshift above 240 and maybe pull over if you are pushing 260.
Fluid has changed since Dexron II of the '70s.

[KD4UPL]

Towing up hill in the heat at 224 degrees doesn't seem like any big deal to me.

[Turtle_n_Peeps]

Magata is correct. That tranny temp is fine.

Think about this for a minute: I have seen people put on extra tranny coolers and add to the "stack". Problem is, the new tranny cooler BTU's will go through the cooling stack and that drives the BTU's of the rest of the stack up..............sometimes sky high!

AC condenser BTU's goes up; the radiator temp will go up. Even the engine compartment temp will go up and that makes everything else's temp go up.

Be careful what you wish for...............:W or at least be careful.

[ib516]

bbaker2001 wrote:
sorry, in valley heat pulling up Yosemite it was running 224. Mataga gmc said that was fine. seems hot to me. I would pull over at times to cool

That's getting up there, but for a few minutes its no big deal.

Additional cooling would benefit you though.

[bbaker2001]

sorry, in valley heat pulling up Yosemite it was running 224. Mataga gmc said that was fine. seems hot to me. I would pull over at times to cool

[bbaker2001]

thanks, yes I see the oem cooler installed, it seem very small. looked at the Tru-Cool 40k but AAmco said he did not think it would install. he wants to sell me the smaller 2400. not sure what all the BTU means, but does bigger always mean better, or is it overkill

[Campfire_Time]

Technically a stacked plate type is best, but tube & fin coolers will work just fine too. The former is more expensive. Both are fairly easy to mount (depending on available space in front of the radiator/condenser) if you have decent mechanical skills.

[_tpc_]

What kind of temps are you seeing? Do you have the additional cooler up front? If you look through the grill you should be able to see it sitting in front of the radiator. If not, you can buy the additional oem one complete with actual trans lines and cooler for less than $100. You can have the dealer do the install, probably for right around $200.

You can do the install yourself, but let me tell you, it isn't for the faint of heart. Disconnecting and reconnecting a trans line a blind location, and thats after you have used your rubix cube knowledge to route the hard line back through everything. If your not handy or lack patience, the money to have it installed is well spent.

If you already have one there though and just want something bigger, it should just mean disconnecting the old, mounting the new and hooking up a couple of short hoses to the existing fittings.

[Iraqvet05]

The Tru-Cool coolers seem to be the best. I almost did a cooler upgrade on a NBS 1500 Silverado but sold the truck for my 2500. Anyway, here is a link to an install that gives you the size perspective on the Tru-Cool 40k linky