3:55 to 3:52
Thread Starter
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Member
Joined: Dec 2001
Posts: 55
Likes: 0
From: Amarillo TX
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.
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.
Senior Member
Joined: Mar 2001
Posts: 4,506
Likes: 6
From: Puyallup, WA
bmsgolf:
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
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
Registered User
Joined: Mar 2000
Posts: 513
Likes: 0
From: Lebanon, TN
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.
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.