Cooling System 1500 vs 2500

[clubhouse]

I’m coming back to my favorite people for a quick question. I’m amazed at what this forum knows so I’m confident you will know the answer to this.

Does a Chevy 1500 vs 2500 of the same year have the same cooling system? I can’t seem to figure this out online or in the GM forums.

My issue, once I sold the TT I thought there was no need in keeping my 2007 LMM Duramax since I wouldn’t be towing heavy or frequently. I now have a 2008 Chevy 1500 5.3L 3.73 4-speed w/ 95k miles. For comparison the Duramax had 140k miles. So from my perspective I got a year newer truck with ~40k fewer miles and pocketed $5k. Thought it was a smart move, now I question it or maybe just miss the HD truck.

For the most part the 1500 truck meets my current need, except I think the temps I see are to high when towing my 3500# 24’ pontoon boat. I’m well within spec; the truck has the factory tow package with transmission cooler; yet last week I saw temps climb to 230 on one particular 8 mile 9% grade. The transmission wasn’t hunting for a gear, I just put it in 3rd and slowly climbed the hill (35-40mph). Engine temp held right at 225 which was less of a concern. Ambient temp was ~90*.

Being the first “real” tow on this truck all fluids were changed Prior to the trip.

Not liking the trans temp I thought maybe an issue with the cooler so I had a transmission shop take a look. They said all was fine, fluid looked decent and not burned, no clutch slip yet confirmed 230 was hot. Went ahead and did a second pan drop/filter change on the transmission thinking that a second drop would help get more old fluid out and new fluid in and might help temp.

Today, coming down the same hill, in 3rd gear holding 45-50 mph, transmission hovered right at 200-205... I was feeling good. Then during a 45 mile flat highway run home I saw trans temps get 215 and engine temp 230. Ambient air was 100*. This just seems to hot.

There is no way I need another diesel; but now I’m wondering if a gas 2500 has better radiator & transmission cooling than a comparable 1500 and what I’m seeing is not an issue with my truck per se, rather the difference in a 1/2 vs 3/4 ton.

[tjpolsin]

Your transmission is running 115 to 140 deg above ambient while towing.
search out a GMC forum board to check comparative numbers for similar transmissions.
One bandaid to consider when you are towing in hot weather is to slow down and run in a lower gear. Your engine fan will run faster and your transmission will be running at a lower load. You will then have plenty of time to enjoy the scenery and mentally calculate gas mileage.

To answer your question. No, a 1500 and 2500 will not have the same cooling systems for the simple reason that the engine/transmission combination in each truck is different.
Cooling systems are designed for the components to be cooled, not the vehicle.

good luck.

BTW, 3500# is well within the range of a 1/2 truck.

[tjpolsin]

I just saw that you have a 2008 truck. Your water pump might be near end of life. and/or your radiator and trans cooler might be getting plugged up with age.