Gearing to go (diff)

[77JimmyMan]

Ok guy and gals, I have a 77 Jimmy with stock 3.08's for gears, TH350 and a NP203. I have a 4" lift and Im running 33's. The motors a fresh mild 300 horse or so rebuild. So ya this beast is pretty sluggish, not exactly what I was hoping for after the motor rebuild. So now its time to spend some more money swaping out gears (looking to buy a soft top too, 500 bucks, ouch). Im looking to get either 3.73's or 4.10's. Personal opinions? Any incite would be nice. Its mainly city driven with the ocasional highway trip (well it hasnt been on the highay for more than a few miles in a while but a few 200mile trips are in the future) some beach trips and the ocasional romp in the woods. Would I possible notice a increase in gas mileage (no im not crazy) just for the fact that I woldnt have to dig my foot into it to get it moving. Also while I have your attention: Any secrets on how to make the steering track better, get a little more response out of it. The front end was proffesionaly alligned so I assume theres nothing wrong down there or they woulda said something. It just seems to wander too much, and the wheel never seems to be in the same up and down posistion twice. Would upgradeing to a newer steering box help? If so which one should I go hunting for (year wise). Thanks in advance for all of your answers. ~Mark~

 

[fortcollinsram]

For the type of driving you descibed, I'd aim for 3.73 gears...should do pretty good with 33's...As far as the steering is concerned, I'd replace your tie-rod ends, get a steering box frame brace form ORD, check your ball joints and replace in neccessary, and check your drag-link ends for severe wear...I replaced the tie-rod end on a friends truck w/ him and it helped TONS...my steering is pretty loose, but I know I need new ball joints and I am going ot get an ORD frame brace very soon...

Chris

 

[Hossbaby50]

I am running 3.73's with 32 inch tires. I have a 300hp GM crate motor, and my truck runs pretty good. My truck will move pretty good for being as big as it is. I would have to recommend 4.10 if you don't run alot of highway. This way your truck will run good threw the RPM band, and if you decide to go to bigger tires you don't have to regear again. I am regearing this summer to 4.56, but I have overdrive, and I plan on 35" tires, and possibly 37's.