Rear diff swap compatibility

[Smitty Smith]

Hello guys, I'm brand new to the forum and need to ask a question before purchasing some parts for my Tahoe.

I'm upgrading from 3.08 gears to 3.73 in order to get better towing performance. Was going to spend $800+ to rebuild both front and rear and install new ring and pinion, but decided to see if my local salvage yard had replacement units cheaper.

They had the direct replacement front diff for $150, but the rear diff they had was from a 4-door "hoe". I'm not sure if it will bolt into my 2-door but it sure looks like it will. The only difference I'm aware of is that the 4-door has a sway bar and bigger brakes. Will this diff bolt up and work in my 2-door? I need to decide by Wednesday.

Thanks

---------- Post added at 09:22 PM ---------- Previous post was at 07:30 PM ----------

Sorry. Forgot to add, this is a '96 Tahoe, 2-door, 4X4.

 

[Yukulele]

I would assume that a 2 door rear and a 4 door rear should bolt right in, same axle width, both a 10 bolt i would assume, the gear ratio may be different prolly has 3.55 in the 4 door so that could be a + for you. Before you buy anything check the gear ratio, and take measurements of the leaf purches on both rears, more than likely should be the same

Just my .02

 

[clean454]

yea everything should be the same the breaks if im not misteaken are only bigger on the suburbans i think the regular tahoe 4dr is the same as a 2dr

and make sure u DONT put a different gear ratio in the rear then the front if ur gunna change the ratio do both

 

[steamroller]

A better upgrade would be a 6 lug 9.5" 14 bolt out of a 3/4 ton or 'heavy half' truck


On the 10 bolt the only difference is the sway bar and 11'' brakes like you said and getting the sway bar and brackets might be a good idea if you're gonna be towing alot

 

[Smitty Smith]

The front end I already bought has 3.73 gears and this rear end also has 3.73's. I'm well aware of what would happen to my brand new tranny rebuild if I were to put different ratios in there. OUCH!

At first, I was turned off to the idea of using the swaybar on the new rear end but the more I think about it, I think I might actually install it in my 2-door because all this truck will be used for is daily driving and towing my boat to the coast. I have a '75 Jimmy for offroading.

Thanks, fellas, for the advice and I found another thread after I posted this one last night where another member has done this swap and it worked fine for him, so I'm good to go.

@ Steamroller, I wish I could find one of the 14-bolt rears but they are scarce around here.

 

[TigerEyz3]

I would assume that a 2 door rear and a 4 door rear should bolt right in, same axle width, both a 10 bolt i would assume, the gear ratio may be different prolly has 3.55 in the 4 door so that could be a + for you. Before you buy anything check the gear ratio, and take measurements of the leaf purches on both rears, more than likely should be the same

Just my .02

Don't think 3.55 gears were a common option. Mine has 3.42 gears, and I believe the 4wd came standard with 3.73s in the later year options at least.

 

[retorq]

So instead of upgrading and fixing your existing rear end, that you know for sure fits, you are going to get a junkyard rear end with god know how many miles of abuse on it, not 100% sure if it's 100% bolt in and just throw it under your rear end now without rebuilding that??

 

[Dlong30]

I would assume that a 2 door rear and a 4 door rear should bolt right in, same axle width, both a 10 bolt i would assume, the gear ratio may be different prolly has 3.55 in the 4 door so that could be a + for you. Before you buy anything check the gear ratio, and take measurements of the leaf purches on both rears, more than likely should be the same

Just my .02

3.55s are popular in stock ford trucks... chevys are ALMOST always 3.42 and 3.73s

 

[Smitty Smith]

So instead of upgrading and fixing your existing rear end, that you know for sure fits, you are going to get a junkyard rear end with god know how many miles of abuse on it, not 100% sure if it's 100% bolt in and just throw it under your rear end now without rebuilding that??

Noooo. I'm gonna crack it open this weekend and change the axle seals and rebuild the brakes completely. Hopefully I won't find anything else inside after I open it. This diff has far fewer miles than the one currently in my truck and the 11-inch brakes are a plus for the towing for which I'm building this truck.

I found another thread in here from someone who's done exactly what I'm doing and the 4-door rear diff bolted right up to his truck. I don't have the hanger hardware to install the sway bar at this time so I'm leaving it off for now.

 

[justarigger]

Whats up guys . This is my first time posting I'm a newbie and new to owning a hoe. love my hoe hate the last owner. no oil in the rear end so I just went through this and guess what I'm doing it again. I have a 95 two door after finding a rear end for the right price I installed it a it lasted three weeks and this is what I learned. A four door rear end will fit perfect 3.42 posi bigger brakes always a plus and sway bar is a good thing for daily drivers. one thing I recommend is installing new seals if you replace your rear end with a used one or you my be doing it twice like me, bad shaft seal . VERY IMPORTANT IF YOU GO FROM A 10" TO A 11" BRAKE DRUM
YOU MUST USE THE 11" EMERGANY BRAKE CABLE. reason the spring on the 10" is shorter and applies to much pressure on brakes . trust me . I hope this post will help some one . Like you guys have helped me . thanks