itchy2000

What is the normal operating temperature of the 2007 LTZ 4x4 auto transmission when used in 2WD ??

I keep seeing it operate in the 165 - 175 degree range when not pulling a trailer or doing anything out of the normal..

I think it has a trans cooler as well....

Doesn't that seem high ??

ZX1100F1

Not for an LTZ, you did say that it is an LTZ correct?

So long as your under 200 (not towing) you're fine, there is no problem.

RedBoat

ZX1100F1, What if it's not a LTZ? Mine is a LT and I normally drive with the odometer reading on the display thenand all of a sudden the display changed to "transmission temp 175".
I was not towing either just driving at 75mph down the highway, whats up with that? I was going to see if it popped up again and if so then take it in. What do you think or is this normal?

itchy2000

Yes it is an LTZ.... Why does that make a difference ?? Does the LTZ have a different transmission that runs hotter ?

kpanza

No, same tranny for all Tahoes...and anything under 200 is fine.

Auburn

What is the ok temp for an LTZ when towing? I asked my service guy about a transmission cooler, but he didn't seem to think one was needed, but he didn't know the ok temps for the vehicle when towing. I live in the south so I figure the transmission will get pretty hot when towing. It gets in the 190 area without towing.

ZX1100F1

All new 2007 Tahoe’s use the GM 4L60-E transmission.
The normal operating temperature is 175 - 200 degrees F

If you are towing or climbing steep grades in summer heat you may notice that your transmission temperature will exceed 200F, keep in mind that heat kills transmissions.

Generally speaking anything hotter then 225F is getting into the dangerous zone, once your transmission gets over 300F it will fail normally within a few hundred miles.


So keep an eye on your Tranny temp gauge and if it goes over 225F then I wouldn't waste any time adding a cooler, just be careful as I have seen many poorly installed coolers develop leaks and smoke tranny's.

Auburn

Thanks for the info. My service advisor was advising against the transmission cooler for the same reason (leaks and causing more problems then helping). He wasn't sure of the danger temps and I just needed to know what to look for.

kpanza

Ah, if you have any skills at all, installing a cooler should not give you any problems. I have installed trans coolers on many of my vehicles, never had a leak or other problem. On my 87 K5 (rockcrawler with 42s and one ton axles, etc), I use the B&M cooler for a motorhome application, and I have an electric pusher fan mounted to the front of it! Yeah,with the 42s and slow moving I need all the cooling I can get... But I wouldn't be afraid of installing one - or find a reputable tranny shop and have them install it for you, it's not rocket science. Just my .02

If you wanted to stay "GM" parts, just look up the part number for the cooler they install with the Optional Heavy Duty Tow package...otherwise B&M makes good ones (stay with the "stacked plate" design vs. the finned ones)

Stingray

I would of thunk these things were already hooked up to a trans-cooler.