How would my truck do with stock size tires?

[mike.germann]

I've had this on my mind for a while. I was wondering how my truck would perform if I chose to go back to regular-ish size tires.

I have 38's now, with 4.56 gears, front/rear

I'm considering the tire change after this winter season. I didn't buy a big@$$ truck for nothin. hahaha.

I'd probably go with a medium A/T or something, I'm not trying to give up the off-road look, just considering less aggressive tires, and I'll keep the same rims (18" MT's). I just didn't want to do it without knowing how my truck would handle it.


What would be the changes in power? Performance? Economy? Towing ability?


Less strain on the trans = definite upside
I'm assuming my acceleration would be better?
Towing ability would go up?

 

[rammertide07]

I'd say increase you towing, acceleration....decrease fuel economy and top end speed.

 

[mike.germann]

Fuel economy would go down? I guess that makes sense. Low end torque seems like it would increase. Is that an accurate statement?

 

[mike.germann]

How would the my transmission respond to it? Less weight = easier work is my logic. Yes/no?

 

[rammertide07]

Fuel economy would go down? I guess that makes sense. Low end torque seems like it would increase. Is that an accurate statement?

Probably be better for around town (lot of stop-and-go's) but I wouldn't think so for high highway speeds And maybe it would make more transmission heat at higher speeds. I have no idea how it would affect your shifts. Did you change any shifting points when you went to bigger tires?

I'm no expert on this....so will one please chime in

 

[mike.germann]

I have the DP F5, but I couldn't tell ya if the shift points were changed.

How could I tell, if they were?

 

[rammertide07]

I have the DP F5, but I couldn't tell ya if the shift points were changed.

How could I tell, if they were?

I really dont know. But a guess....if you didn't specify your tire size and/or gearing, then they probably programmed it for stock tire size. So if your gearing-to-tire size ratio is correct for STOCK....then the programming is right for your current set-up.

 

[BJS]

Given the gearing I would not go less than a 35 to 37.

I can say that I want an extra gear on the top for my 33's with 4.10's I'm actually considering 35's when I replace my tires to help compensate for the gears when running highway speeds.


As rammertide mentioned highway mileage will suffer since you'll be spinning the engine faster

 

[mike.germann]

Is there any resources that tell you what RPM's your truck SHOULD be running at, according to tire size and gear ratio?

 

[rammertide07]

Is there any resources that tell you what RPM's your truck SHOULD be running at, according to tire size and gear ratio?

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