Ok so I recently put 33"s on my 3.0, which has stock 3:73's....Needless to say it now drives like a freakin tractor on the highway. Aside from that, what REALLY pisses me off even worse is my fuel mileage has gone to SH*T.

Im definately considering re-gearing to 4:56's soon I have the cash, and as I understand that will put truck back to stock feeling right? (peppiness restored) But, equally important, will it also put it back to stock fuel mileage?

While im saving for the gears though, how much of a difference would it make to add a tuner, would that give me some power back in the meantime?
And which tuner is the one for my truck, is it the xcal everyone talks about?

Thanks guys

 

Xcal 3 is the one you want. 4.56s should bring it back close to stock for you.

 

your idea is exactly what im goin for

 

with a manual trans go 4:10...i get 20+mpg. with 32s and 373 i was getting 19

i hope you get an 8.8 to regear, or better yet buy a jy one with 4:10s

 

with a 3.0L and 33s go with 4.88s to get the mileage and power back. 4.56s would be perfect with the 4.0L but the 3.0L wants to rev more.

 

Are you kidding me, 4.88s is way to high. 4.88s would be right for 35s, with 33s it would destroy your mileage though.

 

dude with a 5speed im running 2800 at 70 with 4:10s

4:56 would be like 3k or so which is too much for economy and 4:88s um no

 

yeah 4:88's is too high. We had this debate on another thread and the majority agreed 4:56 would be the best match for my truck, 4:10's wouldnt be worth the trouble and 4:88s would rev too high and kill my mpg.

4:56 will get me closest to stock and thats what Im shooting for...

I do very little highway driving so for around town I think 4:56 will be plenty...

 

For an engine that has a torque peak of 3750 RPMs you think revs are a bad thing? To get the best mileage you want the engine to have to do the least amount of work. 4.88s and 33s will cruise around 3000 RPMs at 75-80 MPH... Install a vacuum gauge and try the different combinations and tell me which one gives you the most vacuum when cruising.

 

I run 3000 RPMs at 75-80 with 32s and 4.10s, I highly doubt he will do the same with 33s and 4.88s. I don't have personal experience so I could be wrong but I just don't see that happening.

 

I ran 4.88's with a 4.0L SOHC and 33's, and was running around 2850rpm (iirc) at 70mph. It worked okay, fuel mileage wasn't great with 33's, body lift, yakima roof basket with tire, etc. But it had great power, and worked awsome around town and off road. If I did were to do it again it would be 4.56 gears for that setup.
I would definitely go for 4.56 with the 3.slow.

The tuner will help some, but in my opinion the gears should go first. I got a decent power increase from James Henson's Xcal 2, but a big part of the performance was the shift program, but you have a manual. I had better increase in driveability from the gears than I did the tuner. However, with the tuner, I could recalibrate the speedometer.
Which brings up a good point. If the speedo is not re-calibrated, your going faster (and further) than indicated, so you mileage isn't as bad as you think either. Quite..

 

That doesn't sound right. In fourth gear, with 32" tires and 4.10 gears, you should be running at 3000 RPM at 70mph. I forget 5th gear ratio but I think it would be more than a 200 RPM drop. Is your speedo properly calibrated?

 

if youve already got a 8.8 i have some 4.10's for sale lol just letting ya know.. if thats the path you choose to go with

 

Whoops

 

were did he say anything about it being for a d35 or for a 8.8? or for both?

 

Oh whoops wrong thread lol, sorry about that

 

yea i was like errrr.... lol

 

I am running 33s with 4.10s and a auto tranny, once I figured in the speedometer change with the mileage I was getting per tank of gas. I actually did not drop any MPG. I think everyone thows on larger tires and thinks their fuel mileage went to $%it but it really doesn't when you do the math