5.3L with 35 inch tires?

ugaDAWGS09 · June 19, 2019

Anyone running a 5.3L 8 - speed transmission with 35 inch tires? Just wondering how the transmission operates with the taller tire height? I know the speedometer will be off but how about towing capacity and MPG? Any numbers you could share with me? The tires/wheels that come stock on the 4WD model just don't look big enough for the truck.

Kylebr1 · June 19, 2019

1 hour ago, ugaDAWGS09 said:

Anyone running a 5.3L 8 - speed transmission with 35 inch tires? Just wondering how the transmission operates with the taller tire height? I know the speedometer will be off but how about towing capacity and MPG? Any numbers you could share with me? The tires/wheels that come stock on the 4WD model just don't look big enough for the truck.

I have 295/65R20 on my truck 2016 sierra 5.3l 6 speed and the power is fine you obviously loose a bit of juice because of the bigger tires but not bad at all . My mileage is fine i am doing 15.8L per 100km at the moment

I drive 100 km a day to and from work with no issues . Towing has not been hurt that i can tell so far i am usually towing my Camper and boat with ease .

Sierra Dan · June 19, 2019

The 5.3 is plenty of engine for 35" tires if you have the proper gearing. You will probably need at least a 6" lift to clear 35" tires.

What axle ratio do you have ?

1 hour ago, ugaDAWGS09 said:

Anyone running a 5.3L 8 - speed transmission with 35 inch tires? Just wondering how the transmission operates with the taller tire height? I know the speedometer will be off but how about towing capacity and MPG? Any numbers you could share with me? The tires/wheels that come stock on the 4WD model just don't look big enough for the truck.

ugaDAWGS09 · June 19, 2019

The new trucks come with the 3.23 axle ratio.

arsmitty86 · June 19, 2019

I don't have any trouble. It's not as fast as my mustang was but she moves just fine with the hammer down. Mileage is okay too. Getting 17-19ish in mixed driving so no problems there.

Sierra Dan · June 19, 2019

40 minutes ago, ugaDAWGS09 said:

The new trucks come with the 3.23 axle ratio.

If you are talking about the Trail Boss then yes it is only available with the 3.23

Otherwise another package could include the 3.42 which is better gearing for a 35" tire setup.

asalinasz39 · June 20, 2019

20 hours ago, Sierra Dan said:

If you are talking about the Trail Boss then yes it is only available with the 3.23

Otherwise another package could include the 3.42 which is better gearing for a 35" tire setup.

Yup that I was not happy about when looking into my AT4...had the 17 ltz z71 with 8speed/3.42 and 5.3 and ran 33s (62lb) tires with ease.

Want to run 34s in the future again 62lb tires with my 5.3/8speed/3.23 combo and I am sure mpgs will go down by 1-2pmgs plus loose some power. My only hope is adding the GM exhaust/air intake performance and gain some power back. I don't tow though so really it would be for mpg recovery.

Hopefully the Trailboss owners chime in here as I have seen some adding the 295/70r18 tire (34.3") and the 19s TB are standard with 3.23 gears and 5.3 8 speed.