I just put larger tires on my truck and it changed the gear ratio to a 3:52 from a 3:55 Will this affect my towing much? How should I address this?

 

bmsgolf,

i think you'll probably be ok...LOL, Rich.

 

Just get in and go. That is such a small change I doubt you will ever notice it.

 

Hey Hikerrich,
You have the exact tire size I have on mine. Was your original tire size a 255-70-r16? I just noticed a tremedous difference in towing my travel trailer when I upgraded to larger tires.

 

How did you figure you're only at a "3.52" gear now? According to the "gear calculator" I tried, you are now at what would feel like a 3.38 gear ratio. You would need a 3.73 to make it feel like "stock" again.

I too have the 265/75/16 tires now. Up from the 255/70/16 "door panel spec'd tire" but my rig actually had 235/70/16's on it from the factory.

At any rate, I figured my speedo and odo where off by ~ 5%. Did this by counting mile marker posts and seeing how far off my odo was. Turned out I would pass by only two mile posts, but my odo said I had only passed 1.9. So I was 1/10 of a mile off after only two miles or 1 mile for every twenty or twenty miles for every hundred (5%).

When I changed the VSS gear from the stock 20 tooth to a 19 tooth, that brought everything back. It's still just a tad off, but now I can go past eight mile posts before my odo is the 1/10 off.

I still have the 3.55 gears but noticed that the driveablity really improved when I changed the VSS gear. My theory is that it's tied directly to the computer that controls "everything" on these rigs, so since it's now registering a "near" correct speed, everything else is now within specs...... Again, just my theory and my method to determine how far off my speedo was......

Your mileage may vary

 

bmsgolf,

yep, i had the 255's at first. i, too, noticed a small change when towing after going to the larger tires. we did gain almost 2 inches in tire height which is pretty dramatic when you're starting with a 3.55 gear. Rich.

 

Thanks for your help. I put in a 3.73 gear and that put it back to normal.