Need help approaching this

carrmann · December 28, 2013

I just bought my 2011 Chevy Silverado 1500 z71 crew cab. 5.3, g80, gu6. Love the truck. I will be towing a apprx 8000lb (loaded) 20ft enclosed trailer from NH to florida in the spring (the truck has the integrated trailer brake controller). I am an experienced tower as well. I just sold my 2005 cummins 2500 (too small for my family and too much truck for my needs). Other than that trip it is well within my needs for towing.

here is my dilemma. the truck came with a 4" readylift installed, and ~35" tires (285/75/18). That changes my gear ratio to apprx 3.11s. Which really is too 'high' for towing that kind of load. My options are to go to a stock tire size for my truck (265/65/18), or go a size or 2 up from there (say a 275/70/18 ~33"). Will the truck be able to handle that load with 33" tires (changing my gearing to apprx 3.32 from 3.42)... or should I go with stock size for maximum torque?

I know the easiest route is stock tire size, and the truck would be adequate for my trip to florida with that trailer. However, I like the 4" lift (it looks good). I really dont want to take the 4" lift off and go to stock tire size if the 33" tires will do the trick (especially since that lift really should only have 33s per their website). Hopefully this makes sense, please ask me questions if you have any! I hope someone can help me out here with personal experience or general knowledge of how well these trucks tow. Also hoping the 33s will improve F.E as right now Im only seeing high 14s which is sad.

picture of the truck.

mike94silverado · December 28, 2013

It's going to be a lot different than towing with the Cummins thats for sure... before you do anything, can you hitch up and tow for a couple of hours and see how it is? I towed an hour away and back on my "test Drive" just to be sure I was buying the right truck....

carrmann · December 28, 2013

I'm afraid its already purchased lol. Will definitely be different than a tuned Cummins haha.

I towed my 24ft enclosed with about 1klbs inside for an hr with my old 2005 z71 3.73 auto 5.3 and it handled it! Didn't much like the mountains but it did ok and was able to maintain 55 uphill.

This truck has more power and better gearing stock. What I'm trying to figure out is, will I be able to tow with 33s or do I need to go stock height

carrmann · December 29, 2013

well I screwed up. it actually has 275/70/18s kelly safari tsr. oops. it still feels really high geared, downshifts a lot at 65. however the front tires are really chopped up (bad alignment im assuming). so that may be contributing to the bad mpg etc.

Im going to look at 265/70/18s. 1" taller than stock... hope that is going to work out. not going to go with such an aggressive treaded tire either.

Ramin258 · March 4, 2014

IMO 265/70R18 will look bad with a 4 in lift. Have you thought about keeping the tall tires since they look good and re-gearing the front and rear diffs to 4.10's, maybe even 4.30 or 4.56?

txab · March 4, 2014

Re-gear

carrmann · May 10, 2014

so my plans have changed... and the trailer is actually going to be a loaded 24ft trailer with a car in it as well as my household goods. guessing around 10000lbs. which.. is out of my max tow rating. can I do anything to make that ok?? I have a weight distribution hitch for it. is the max tow capacity based on braking, accelerating, or just an overall rating? I'll be towing to florida during the summer and possibly through the pocono's as well as any other mountains I may run across using the interstate.

I thought possibly airbags to help with the load? the trailer has brakes as well (of course)

06_GMC · May 11, 2014

I don't think very many of us are going to tell you to of it. But they made your truck but with the 6.2L in it and it could tow just over 10K if I remember correctly. Obviously some things were changed but as far as the truck itself as in frame and body not much is different. The truck will do it but you risk burning up drivetrain parts. If it were me I would re-gear instead of tires and do a set of airbags and a weight distributing hitch and she should do just fine. Is it the best idea? Maybe not but I would do it if it was me personally. I however won't tell you to do it. The decision is yours. Good luck and keep us posted.

sillywillie07 · May 12, 2014

It needs to be re-geared. Not sure why they were geared to 3.11, when stock would be 3.08 or 3.42. I have timbren, suspension helpers in my truck and love them. You don't have to play with air, or think about air leaking out of the bags.

carrmann · May 12, 2014

sorry for the confusion. it has 3.42 gears. it just had taller tires, so it was essentially a different effective gear ratio. I fixed that... put stock size tires back on.

i do have the weight distribution hitch... guess I'll just see how that works, if its not enough I'll do the airbags as well.