Innerchangable Rear End for 87' Burban

[Stumpy]

I need a rear end for an 87' 1500 Suburban 4WD. I have no idea how to determine the gear ratio. My rear diff cover is missing along with all the gears in the housing. My first question is how to determine gear ratio. Secondly, what other make/models are compatible when it comes to rear ends (i.e. vans). We have a pullapart in Charlotte, NC and they have a lot of vans to choose from...Not many burbans/K5s.

 

[pauly383]

Well , a direct bolt in is any six lug 10 bolt truck axle from the same era , which is not long for this world in a heavy Suburban . My buddy bent his light wheeling with all his camping gear on board .

I would , with a conversion u-joint and new rims , take both matched axles from a 8 lug pickup or Suburban 73-87 in pickups , and to 91 in Subs . If you change both axles at once , you can have matched ratios .

if you wanted to keep your six lug rims , a 14bolt semi floater can be found under some IFS trucks ( light duty 88 and newer K2500 ) , most with 3.73 or 4.10 gears .

As for your ratio , if you have no ring gear to look for the stamping , pull your front cover and look for that ring gear markings ( gear oil is probably ready to go anyway if you keep your front ) .

 

[onetonbb74]

welcome to the board, you can try the for sale forum on here, plenty of half tons getting parted out with axles for sale. Get a membership first though, there is even a regional section you can post in to find an axle. To find the gear ratio, check the glovebox for a option list otherwise i just pull the front cover and count the teeth, both front and rear gears must match for 4wd to work. Then take the small number (pinion teeth) and divide it into the big number (ring gear teeth) and you get a ratio. Ex. 41 ring gear teeth and 10 pinion teeth is 4.10 gears (41 divided by 10). 41-11 is 3.73 gears and so on. Don't get a van axle unless you want to grind off spring perches and reweld new ones on the van housing and shock tabs. Id look for a truck rearend or a blazer/sub rearend, they bolt right in and a truck rearend you need to reweld one shock tab.

 

[Stumpy]

Thanks for the reply and breaking it down for me. I guess the best thing to do is pull off the front cover and count the ring and pinion. I know there are some codes in the glove box, but I don't know how to decipher them.

 

[BGKYK5]

Assuming the axles are original you can look up your RPO codes here:

http://www.73-87.com/chevy_ids/rpomenu2.htm

 

[Stumpy]

Thanks Man!!! I have a 3.73 according to the RPO code of GT4. I looked up G80 (another RPO code I have) and It says "Axle, RR locking type". Do you know what this means?

 

[BGKYK5]

Probably a Gov-Lock "locking" diff.