Determining your rear ????

[BlazinerUp]

I have an '87 K5 with 4 WD, a 350 5.7 L, but I dont know what rear I have. Is there a way to tell what size rear is back there ??? I dont have any of the original paperwork or ownerw manual. All I use it for is to tow my boat, and I want to make sure I have an adequate gear ratio for this. Any help would be appreciated.

 

[outlaw612]

Count the bolts on the diff cover. It will have 10, 12, or 14 bolts. The stock one in your 87 will be a 10 bolt.

 

[Z3PR]

I'm not sure, but I think there is a tag on there that tells you what gears are in it. You could write down your VIN and email GM and ask them. www.gm.com