GMT900 with 4.8 lower towing rating than GMT800

NEFisher11 · February 7, 2014

The other day while in my buddys owner manual for his 2007Gm800 i noticed that the GM800 trucks speced like mine had a higher tow rating. My truck is a 2011 with the 4.8l 4l60e and the tow package. A GM800 speced the smame way was rated for a think it said close to 7000lbs where as mine is only rated for 5500lbs. What is the reason for this? My 4.8l is more powerful than the ones the put in the GM800. It dosen't make any sense to me why GM would derate the truck now i wish i did a little more homework when i bought my truck.

MS3DALE · February 7, 2014

You didn't mention what gear ratios are in the trucks,but the gear ratio changes tow ratings as well.

NEFisher11 · February 7, 2014

Mine and what i saw had 3.42 rear ends.

2017SierraSLT · February 7, 2014

Yeah, that is really low. The same truck with 5.3 and 3.42 rear gears and HD cooling is rated for 9500 lbs.

2017SierraSLT · February 7, 2014

The GMT800's with 4.8 and 3.42 gears are rated for 6500 lbs trailer weight.

NEFisher11 · February 7, 2014

Ok i knew it was higher than my truck. Now i wonder why they de-rated my truck.

2017SierraSLT · February 7, 2014

Not sure. It is possible that GM was having a lot of warranty repairs and decided to lower the published rating. The main powertrain components are almost identical between the trucks. The frame is stronger, and the 4.8 puts out more power in the 900's. My friend with a '12 extended cab 4.8 4x4 Sierra has towed 6000 lbs without a sweat.

NEFisher11 · February 7, 2014

Even more warrant repairs don't make sense. It still had the same tranny as the GMT800 with the 5.3. Just has made me curios. I mean a damn Honda Ridgline has the same towing capacity as my truck kinda a joke if you ask me.

MikeInCtown · February 7, 2014

Even more warrant repairs don't make sense. It still had the same tranny as the GMT800 with the 5.3. Just has made me curios. I mean a damn Honda Ridgline has the same towing capacity as my truck kinda a joke if you ask me.

Why wouldn't it make sense. if you have people hauling the max and it is causing you $$$$ in claims, but you have found that reducing the max by 500lbs will cost $$$ less in claims, what would you do?

NEFisher11 · February 8, 2014

Sense everything in the truck is shared with the 5.3 which is more powerful than the 4.8 i would doubt people where tearing up the mechanicals.

MD Chevy · February 9, 2014

The 800 series 4.8 had more nuts than the 900 series. Check out the torque curves on both. I had an 09 crew with the 4.8 and hated the lack of guts down low. Had plenty of top end though. Not sure if that is the reason behind the drop but it could be...who knows!

CapitalTruck · February 9, 2014

That 6500 might have been for a two wheel drive, do you now have a 4x4? Also, bed length/cab length plays a roll. My GMT-800 2wd 4.8 with 3.73 was rated at 7100. My GMT-900 with 4.8 3.42 rear 4x4 is 5500. It does kind of suck. Having said that, I so rarely tow anything major that it isn't a problem.