Frustrated in Texas!!

[88Racing]

One more question: What motor and do both trucks have the same one?????

[Tuscany FTX]

To my knowledge we both have 3:73 gears. We both have 5.4l engines. The only known difference is he has 17" stock wheels,tires, and I have 305/55/20's. I now have the Nitto Trail Grapplers, but before I was running Toyo Open Country A/T's. Thanks 88 for looking into my prob!

[Tuscany FTX]

88! One more thing. It is like NIght and Day difference. I wouldn't be concerned if it was just a little bit, but it is drastic enough to make you think something has got to be wrong with my truck. When I floor it (WOT) it builds RPM and sounds great, but it is like it doesn't engage. Not that the tranny is slipping or anything because all feels smooth, but it just doesn't go. His puts you in the seat and easily leaves me by 5-6 truck links.

[shotgun]

Boy - that sounds like the torque converter isn't locking up.

Are you monitoring it on the Gryphon?

EDIT:
From page 9 of the manual

COM GEAR

Visual gear indicator: Current transmission gear and torque converter lockup state

[Jackpine]

Actually, I suspect your wheel/tire combination. I think your tires are MUCH bigger than your neighbor's, which reduces your effective gear ratio by a bunch. This is going to make your truck slow off the mark, unless you re-gear to compensate.

If you tell me what size tires your neighbor has, I'll be able to tell you the difference in your effective gear ratios.

AND, I would not expect the TC to lock up at all in a WOT 0-60 run. With that load, the TC is going to stay unlocked to provide torque multiplication.

- Jack

[88Racing]

I'm with Jack on the wheel size.
The stock OEM on the 20's is 275/55r20.
This is the same size as the stock OEM 18 tire once squish is taken in and accounted for.
Peace!

[Jackpine]

IF your OEM tires were 275/55/20s, you've reduced your effective gear ratio to 3.58. You've lost a bunch of "mechanical advantage" and your truck is going to be slow off the mark. Now you can spend more money and re-gear if you'd like your acceleration back.

- Jack

[Tuscany FTX]

Originally Posted by JackandJanet

Actually, I suspect your wheel/tire combination. I think your tires are MUCH bigger than your neighbor's, which reduces your effective gear ratio by a bunch. This is going to make your truck slow off the mark, unless you re-gear to compensate.

If you tell me what size tires your neighbor has, I'll be able to tell you the difference in your effective gear ratios.

AND, I would not expect the TC to lock up at all in a WOT 0-60 run. With that load, the TC is going to stay unlocked to provide torque multiplication.

- Jack

My neighbor is running the stock(OEM) wheels/tires. They are 275/65/18, which is also what my stock wheels/tires were.

[Jackpine]

Originally Posted by Tuscany FTX

My neighbor is running the stock(OEM) wheels/tires. They are 275/65/18, which is also what my stock wheels/tires were.

Uh - you said earlier that he had 17" wheels, not 18's. Can you tell me which it really is? And, is his truck the same model? Because if his is lighter than yours, it's going to be faster too.

I'm going to add that your larger tires DO have more "mass", which means there IS more power needed just to get them rotating (along with the increase in weight they add to your truck, the increased "rolling resistance" due to the larger footprint and the increase in wind resistance you'll see at highway speed due to the larger frontal area).

- Jack