14 5.3 4WD CC vs 18 5.3 RWD EC

[clayp]

My 2014 5.3 4WD CC/SB is in for service work and I got a loaner 18 RWD EC/SB truck to drive. My 14' in on 20" wheels with 275 KO2's and the 18' is on 17" wheels with 255 Generals. The 18 feels like the throttle response is much better and pulls harder, more than I would expect from the weight/4wd drivetrain/tire-wheel difference would suggest. Any thoughts? Both are 6A trannies, and my '14 has the 3.42

[Sierra706]

My 2014 5.3 4WD CC/SB is in for service work and I got a loaner 18 RWD EC/SB truck to drive. My 14' in on 20" wheels with 275 KO2's and the 18' is on 17" wheels with 255 Generals. The 18 feels like the throttle response is much better and pulls harder, more than I would expect from the weight/4wd drivetrain/tire-wheel difference would suggest. Any thoughts? Both are 6A trannies, and my '14 has the 3.42

The smaller and lighter tires make a huuuge difference. I drove two 5.3 extended cab trucks, my truck with factory 22s and a loaner with factory 17s and it’s almost a night and day difference. My truck felt like it was towing a trailer compared to the loaner.

22s are wrapped in a 32” tire. I believe the 17s have a 30.5” tire. So that reduction in gear ratio combined with the lower unsprung weight is what your feeling.


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[BlackHawkZ71]

On 1/17/2018 at 7:56 PM, Bushleaguechew said:

 

The smaller and lighter tires make a huuuge difference. I drove two 5.3 extended cab trucks, my truck with factory 22s and a loaner with factory 17s and it’s almost a night and day difference. My truck felt like it was towing a trailer compared to the loaner.

22s are wrapped in a 32” tire. I believe the 17s have a 30.5” tire. So that reduction in gear ratio combined with the lower unsprung weight is what your feeling.


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You’re also forgetting about the weight of the truck as well. Double cab rwd is going to weigh less then a cc 4wd. Not sure by how much exactly.

 

In my case i was given a 17 double cab short bed, rwd on 20”s with an eco sport tire, here’s the kicker it was a v6. I honestly didn’t realize it was a v6 until i popped the hood. 

 

Now my truck in sig the tires weigh roughly 53lbs or so on stock 18”s plus i have the cc/sb in Z71 trim. 

[Donstar]

Wheel size and weight have a significant impact on performance.  It is often a huge dilemma when choosing between looks and performance.  I added larger 10 ply tires to my last truck and loved the look and rugged feel.  I certainly paid for it in pep and gas!  

[L86 All Terrain]

By reducing the mass your drivetrain has to rotate, you will improve the felt horsepower and torque. Put a 2lb weight on a string and swing it in circles, then do the same with a 5lb weight and see which is easier to get spinning? My E load tires inflated are roughly 20lbs heavier per tire than the stock ones. A lot of weight in today's larger wheels too. The stock 20's I have are considerable heavier than my last trucks 18" wheels. 

['17 Sierra]

On 1/23/2018 at 12:14 PM, 10SierraA.T. said:

By reducing the mass your drivetrain has to rotate, you will improve the felt horsepower and torque. Put a 2lb weight on a string and swing it in circles, then do the same with a 5lb weight and see which is easier to get spinning? My E load tires inflated are roughly 20lbs heavier per tire than the stock ones. A lot of weight in today's larger wheels too. The stock 20's I have are considerable heavier than my last trucks 18" wheels. 

But how much do your E load tires weigh deflated?

Sorry....couldn’t resist..

[truckguy82]

Probably just throttle pedal slack in your ‘14

 

adjustable pedals could also be out further on the loaner, that makes a huge difference in throttle perception

[L86 All Terrain]

On ‎2018‎-‎01‎-‎27 at 12:14 AM, '17 Sierra said:

But how much do your E load tires weigh deflated?

Sorry....couldn’t resist..

According to Boyle's law of constants: 33x12.5R20 has a volume of roughly 3.43ft3  (40psi + 14.7psi = 54.7psi) 54.7psi/14.7psi x 3.43 = 12.76ft3 of volume at a given pressure of 40psi absolute. 12.76ft3 x 0.07516lb/ft3 (specific weight of air at 20c and atmospheric pressure) = 0.96lb per tire heavier, if my math is on. Lol, I would have thought more than that but I guess I need to factor in that I went from a P rated car tire weighing about 43lbs to an LT tire weighing around 70+lbs so I guess most of the weight was right there. I wrestle big transport and equipment tires at work, when inflated to 110psi there is a noticeable difference in weight but maybe more in my head than anything haha.  

['17 Sierra]

47 minutes ago, 10SierraA.T. said:

According to Boyle's law of constants: 33x12.5R20 has a volume of roughly 3.43ft3  (40psi + 14.7psi = 54.7psi) 54.7psi/14.7psi x 3.43 = 12.76ft3 of volume at a given pressure of 40psi absolute. 12.76ft3 x 0.07516lb/ft3 (specific weight of air at 20c and atmospheric pressure) = 0.96lb per tire heavier, if my math is on. Lol, I would have thought more than that but I guess I need to factor in that I went from a P rated car tire weighing about 43lbs to an LT tire weighing around 70+lbs so I guess most of the weight was right there. I wrestle big transport and equipment tires at work, when inflated to 110psi there is a noticeable difference in weight but maybe more in my head than anything haha.  

I actually thought it would be much less than .96 lb but nice work nonetheless! Maybe try Helium....actually, it too will be compressed and leak out rather quickly LOL!!!