3.08 lift options

[Back in a Bowtie]

Ok so any guys lifted with 3.08 gears? Thoughts? I was all set on going with a level kit and 33s but lately ive been liking the idea of 4" BDS with 35s. What are the realistic losses running these set ups on those gears? Right now a gear swap is totally out of the question so that is the first limitation for me. I don't want to turn my truck into something with the power of a 4 banger but I have seen someone as large as 40inch tires on 3.08s. I don't wheel (at most i take it out on the beach, or down the powerlines) so its totally a street truck/ mall crawler.

 

[LongrangeLauber]

It would feel like a 6 cylinder tbh

[Back in a Bowtie]

It would feel like a 6 cylinder tbh

with 35s? Maybe go level and 33s for now and when those tires are shot upgrade gearing and go bigger? Maybe a tune in the meantime?

[LongrangeLauber]

with 35s? Maybe go level and 33s for now and when those tires are shot upgrade gearing and go bigger? Maybe a tune in the meantime?

Yeah I would stick with 33's for now until you can afford a regear. Tune would help. Don't forget that your tow rating will decrease ever so slightly with a bigger tire if you don't have the proper gears

[GRN69CHV]

Drive it around in M4 or M5 and don't worry about it. 4th gear is underdriven, giving you a 3.54 overall ratio, about the same as running a 4L80E with a 4.56 gear set (actually little deeper, 4.72, if they made such a gear set). Mine has 3.08's also. Was bent on swapping the gears, but have just gotten used to running it in manual mode only shifting it into 6th gear at 55-60 mph. Other advantage is, in manual mode, it stays in V-8 mode all the time.

[KMGZ400]

I had a Silverado with 3.08 and I wouldn't run anything bigger then the stock size... It's gonna kill that trans.. Maybe I'd do a level and 285's but no way 35's... I don't even run 35's on my duramax because I don't like the way the drive, stuck with 33's

[Back in a Bowtie]

Drive it around in M4 or M5 and don't worry about it. 4th gear is underdriven, giving you a 3.54 overall ratio, about the same as running a 4L80E with a 4.56 gear set (actually little deeper, 4.72, if they made such a gear set). Mine has 3.08's also. Was bent on swapping the gears, but have just gotten used to running it in manual mode only shifting it into 6th gear at 55-60 mph. Other advantage is, in manual mode, it stays in V-8 mode all the time.

what tire size you running?

[GRN69CHV]

Only running a 32" (275/65-18). 33's would be a no-brainer.

[Back in a Bowtie]

yea i mean i have no doubt in my mind the difference btw stock and 33 will barely be noticeable (if at all). But i wonder if anyone is running 35s and 3.08s that can chime in.

 

P.S. This thing has 3.08 gearing

[GRN69CHV]

What kills the trans is heat build up from running under load at low rpms. As long as the engine rpms are kept up, other than output shaft speed, internals of the trans really don't know what gear is out back. Are 3.08's and a double overdrive trans ideal? No, not with a 35" tall tire. Truck in the picture above, if I was going to the expense of that much suspension mod's, it'd probably make sense to spend the extra $$$ and swap the gears out. I'd probably also do give serious thought to swapping out the 8.25" carrier up front also in the process. New style 9.5" 12 bolt looks to be fairly stout, weak link out back will be the semi-floating design.

[stevencox93]

Thats a show truck not meant to be driven everyday and last forever with that setup like we would use it for. I run 35s but have 3.42s and a tune

[LongrangeLauber]

Personal preference would be a 4.10 gear at minimum. 4.56 ideal with 35's (for the added weight)

[Chris]

Personal preference would be a 4.10 gear at minimum. 4.56 ideal with 35's (for the added weight)

Not just weight. With a taller tire you are reducing the effective ratio. A smaller tire will increase the effective ratio

[LongrangeLauber]

Chris get outta here you know I know what I'm saying haha

[TheTunaHunter]

My truck has 3.08's, 2" RC Level w/ DuraTracs (275/70/18)(E) - basically a 33" and I've lost about 5mpg on the highway. Consistent average on 100mile drives recently is about 20mpg, where as pre level/tires I was seeing consistent mid 20's. Truck doesn't seem to mind and I have no complaints about driveability. The one time I did notice was a 340 mile drive up to Vermont, on some of the long inclines the truck did "hunt" for gears but nothing some manual mode couldn't deal with, I also kept an eye on transmission temps with nothing to cause concern......All that said, I will not be going with the load range e tires again, but will stay with 275/70/18. Not sure I'd be happy with driveability with larger lift.