OK so I have recently put 31x10.50's on my blazer. The stock tires I had were 233/75/15's. My blazer is kinda sluggish now so I'm gonna up the gear to 3.73 or 4.10s.

I have been reading up on changing the gears in the front end and apparently it is a lot of work. You have to remove the front diff and to do this you need to take out the CV axle shafts, undo the tie rods, steering box and possibly some other stuff. This is way above my ability so I'm gonna have to take it somewhere to get it done.

The thought of labor costs really scares me haha. Sounds like it will cost a small fortune. Anybody have a rough estimate of what I can expect?? Anybody here ever had the gears in their front diff changed out?

 

Well I finally went and got an estimate today. I've just been busy with school,work, christmas and everything. So for all parts and laber for both axles it is going to be around 1200-1300 dollars.

I am going to go with 4.10 gears. The reason I chose 4.10s is because 3.73s would be slightly under geared for 31s. 4.10s will be a bit overgeared but if I'm going to drop this much coin on something I want to get some added pep out of it and not just get back to around the stock level. Plus I may eventually go bigger than 31s so this will save me from having to do it twice.

So in case any one else out there wants to get it done expect the price to be in the 1200-1300 dollar range. If you can find anywhere that will do it cheaper you should go for it.

 

Good stuff! What you lose in top speed is gained in torque and the ability to climb.

 

3.73's is what the ZR2's come with stock... and they've got 31" tires...


You'll probably get better gas mileage in the city with those 4.10s, though.

I'm not changing my gears until I can get at least 35's under my rig, lol.

 

yeah I have done some reading on the zr2 forum and a lot of guys would like to run or are running the 4.10s.

They said they gained around 1-2 mpg city driving but you will also loose around that much during highway driving.

 

I'm pretty happy with my 3.42's and my 30" tires so far... If I drive nice, I can still get over 15 - 16 MPG in the city...

Haven't done a proper check on highway mileage in a long time, though...