Hello!

1994 c2500 rwd
454
8 lug
14 bolt rear diff (I believe it is a semi float? so not the gov bomb)

I have been looking into differential options for my rwd truck. I do a fair bit of desert trips / glamis trips / big bear trips / minor off roading in socal area. I would like a locker for the rear diff but am struggling with identifying what my options are.

What would you recommend to get an lsd or some kind of locker in the rear? Entertaining ideas of locker kits to install in current diff, diff swaps, rear end swaps, whatever is somewhat affordable / attainable.

 

Start by checking the RPO sticker on in the glove box - the codes that start with G define the axle gear ratio and whether or not it’s limited slip.

Once you know that, you can find more specific products for your truck.

 

I am not sure about the 2500's, but many of the GM trucks come/came with the G80 automatic locking rear differential. My 2006 Silverado WT RWD has the GU5 and G80 RPO codes in the glove box, meaning a 3.23 axle ratio, and the locking rear diff. Unfortunately, my 1996 C1500 RWD does not - it just has the GU6 code for a 3.42 rear axle ratio, and no other "Gxx" RPO codes.

If you are lucky, you will have more than one Gxx code on the RPO sticker inside the glove box. But from what I read online, the G80 diff was an option on the C/K trucks, and became a more standard offering on the later series (since 1999).

So yeah, the factory locking diff is also nicknamed the "gov bomb", but I've had no issues in 135,000 miles on the 2006 Silverado...

 

just checked - GT5 and G80. sounds like i have the g80 with 4.10s?

 

confirmed it is also a full float.
so 4.10s, full float, 14 bolt g80.

any recommendations for an open carrier and locker that would swap straight in?

 

So you are looking for something beyond the automatic locking that is already going on with the G80 rear diff that you have? My understanding is that it will lock up with there is a difference of 100-120 rpm between the rear wheels. Here is a little reading info:

https://www.autoevolution.com/news/a...ial-94874.html

That said, it looks like you knew this already, and as I've never replaced my rear diffs on my GM trucks, I have no recommendations beyond what I see you already are getting with the same question over at GMT400 forum website. Detroit locker? I personally don't know how much improvement you will see though. That said, you have a heavier duty rear end already (14 versus 10 bolt), so it is less likely to be blowing up on you.