Towing with 33” tires versus 35” tires

[kylenautique]

I’ve been searching around and I haven’t found the exact answer I’m looking for. I’m considering going from 33s to 35s. I have a 98 Silverado 1500 with a RCX 6” lift. 16” wheels. I use BFG TA KO2 tires. My transmission has been tuned. Torque management and abuse mode are turned off. Shift points are corrected to 33s. 3.73 gears. If I go to a 35” tire and adjust the shift points, am I going to regret it when I’m towing my boat and driving up mountain roads with 3.73 gears, or will I not really notice much of a change?

 

[yevgenievich]

Change to 4.11 gears and tow in 3rd.

 

[Jesse_Wenting]

I'm kinda surprised you don't find the 33s a bit lacking with 3.73 already tbh. I like the feel of 31s with 3.73, and I'm currently running 33s with 3.42 with plans to re-gear all the way up to 4.11

For 35s, especially if you're towing with any regularity, you should be considering 4.56 gears.

 

[kylenautique]

I always tow in 3rd regardless. So its a pretty big difference eh? I mean, I went from the stock 31" tire to the 33, and with the shift point corrections in the ECM it felt the same as the stock tire. Adjusting the shift points don't do enough with 35" tires?

 

[Jesse_Wenting]

I always tow in 3rd regardless. So its a pretty big difference eh? I mean, I went from the stock 31" tire to the 33, and with the shift point corrections in the ECM it felt the same as the stock tire. Adjusting the shift points don't do enough with 35" tires?

Sorry forgot to mention I'm still running the factory tune. PO put the 33s on without any tune and I haven't gotten around to it yet. Got the feel for 31s with 3.73 from my dad's stock 96 K1500

Don't know what engine you've got, but how's your low end torque? Also highway speeds if I want to pass someone I generally have to go into 2nd at 4500ish RPM for the duration of the pass. I remember my dad's 96 being able to make highway passes pretty easily in 3rd. Will tuning the shift points make that big a difference?

 

[kylenautique]

Sorry forgot to mention I'm still running the factory tune. PO put the 33s on without any tune and I haven't gotten around to it yet. Got the feel for 31s with 3.73 from my dad's stock 96 K1500

Don't know what engine you've got, but how's your low end torque? Also highway speeds if I want to pass someone I generally have to go into 2nd at 4500ish RPM for the duration of the pass. I remember my dad's 96 being able to make highway passes pretty easily in 3rd. Will tuning the shift points make that big a difference?

Looks like our rigs are similar. I also hydroboosted my brakes. 1998 k1500 with the Vortec 5.7. Nothing crazy. Spider injector upgrade, electric fans, stock ECM. Adjusting the shift points, removing abuse mode and reducing torque management is a huge game changer. I don't go into OD until 58mph. I have no issue passing anyone. Removing Abuse mode and TQ management will make that easier. You hit the gas and your truck actually goes! Keep in mind, if you drive your truck hard (burnouts and stomping on it constantly driving it like you stole it) and you have a stock 4l60e, if you remove abuse mode and all of torque management, you are going to shorten the life of your transmission.

 

[thegawd]

Tire Size Calculator - Compare Tire Sizes | Tacoma World

Tire size calculator compares diameter, width, circumference and speedometer differences for any two tire sizes. Supports tire sizes in metric and inches.

www.tacomaworld.com

here, play with this tire size calculator. it should awnser most of your questions... going from 33 to 35 will absolutely be detrimental if towing is your goal.

big tires help throw mud off road, oem size tires keep you in the zone of both fuel economy and torque.

theres also tiresize vs gearing charts but they are only useful with towing in 3rd at a 1:1 ratio. put it in overdrive and the ratio is messed up.

@Erik the Awful made a chart for the 4L60E and its overdrive gear.

 

[0xDEADBEEF]

You'll notice it unless you regear. Any difference in tire radius has an exponential effect. Tire mass is linear.

Shift points won't really do anything to offset the increased inertia of the wheels/tires.

 

[thegawd]

Exactly!

 

[Jesse_Wenting]

Looks like our rigs are similar. I also hydroboosted my brakes. 1998 k1500 with the Vortec 5.7. Nothing crazy. Spider injector upgrade, electric fans, stock ECM

Very similar by by the sounds of it yeah. I'm currently running a lil 305 (part of the trouble with passing I know), original 5.7 broke a rod and I'm waiting for the summer months to build the one I've got sitting in the shed. Been looking into electric fans extensively recently lol. I'm not gonna lift though, happy with the extra inch or 2 of step up height I get from 33s.

Adjusting the shift points, removing abuse mode and reducing torque management is a huge game changer. I don't go into OD until 58mph. I have no issue passing anyone. Removing Abuse mode and TQ management will make that easier

What exactly is torque management, and what does abuse mode do?
I am running a near stock 4l60e, only big upgrades I've done so far are a hardened sun shell and SONNAX pressure boost valve. This truck is my DD so I'm not looking for insane numbers. When I build that 350 in the shed I'm hoping to be around 350hp but not much more