what gears do i need on differential?

[raycow]

Originally Posted by gdogg14

I would like to cruise down the road 70mph @ no more than 3000 RPM, I may get that with a 3.07 raito but will it have enough power to get itself going from a dead stop.

Easily. 3.07 was a factory option on these trucks, and GM doesn't like to sell parts combinations that are going to result in unhappy customers.

Ray

[ERASER5]

I agree with Ray. The 3.08 (3.07) was probably the most common C10 ratio out there. This is not a hot rod gear, it is a mileage gear, but it still gets it done. I ran 2 different trucks on 31" tires with no problems for years.

Ray and I agree on the easiest way to check gear ratios too. Simple, fast, non-intrusive, accurate.

[camaney]

ok so ihave 4.11 gears and im thinking on puting 3.40s do u think that i will have any problems if i do? also what other driveshaft from another vehicle will fit whit out cutting or anything?(shortbed). i never done gear changing before but i seen videos they use some kind of tool with a gauge dial. do i realy need that tool or should pay someone who knows how?

[Longhorn Man]

if you have no idea whats involved, then I'd recomend paying someone. The problem is, it won't be cheap.
Even if you had the tools there for you, this isn't something most people should try. If you don't get it dead nuts right, it'll chew them up and spit them out, and damage other stuff at the same time.

[LONGHAIR]

Yeah, what he said^^^

Gear swapping is not a job for a novice. Pay a pro, it will still cost less in the end. Destroying parts and having to pay to fix it after it fails, is expensive.

[raycow]

You will come out ahead by buying a complete rear end with the ratio you want. This will be much cheaper than buying gears and paying someone to set them up in your housing. The rear end swap is something you can do yourself without needing any special skills or tools.

When you are done, you might even be able to sell your old rear to someone who wants the ratio that's in it.

Ray

[292farmer]

whats wrong with the driveshaft?

[camaney]

thanks my mecanic coute me$150 for the job i think is cheap where can i buy the ring and pinion? i want to change the drive shaft with something lighter like my newer gmc is some kind alloy metal

[raycow]

If you want to install 3.07 gears you will also need to replace the differential case. This is the part that the ring gear bolts to. Your mechanic will probably not want to press off your old bearings and re-use them on the new parts, so this means you will need new bearings. You will need new seals and gaskets also. At this point, you are way beyond the cost of a salvage yard rear.

Ray