This is my first post so I'm sorry if it's not in the right place, I have a 01 blazer and the front end locked up on me. and I narrowed it down to my front differential ( I pulled the front drive shaft and it didn't help)

So my question is if i go to a pick n pull yard, and get a front diff is there anything i need to look out for because i dont know what gear ratio myn is. Or are all of them interchangeable? I looked on the front diff and can not find and code or anything

01 blazer
2 door
​​​5 speed






I added the vin if anyone knows about these thing well enough to give some info

 

As for the gear ratios, you will need one that matches yours. You can find out what yours is by looking at the RPO sticker that is in the inside of the glove-box door. You can look up what these are to double check what I included here for the 99 model year.

GU4 3.08 Ratio
GU6 3.42 Ratio
GT4 3.73 Ratio

Is your Blazer a ZR2 model? This code would also be on the glove box sticker. If it is a ZR2, it might have 4.11 ratio gears.

Otherwise, I'm pretty sure the front axles are pretty much the same but I have never had to replace mine. Hopefully someone else can chime in and fill you in on that.

 

I can't check my glove box that was my first step but a previous owner tore that off for some reason its just the white sticky side
and no its a base model with a 2.5 inch lift and tires

 

OK. So then the next step is to find a VIN decoder that will then create a list of all of your RPO codes. I did this a long time ago with my Blazer and it was super useful to have. Unfortunately I forget where online I was able to do it. Perhaps a GM dealership could do it for you too.

 

Well, if you take your old differential and gut it you can sell those cast iron case halves on Ebay or Amazon, Facebook or what have you. They'll get you some more funds toward your SFA swap.