Need diff and tranny info for 98' K1500 z71 pick up please !

[That90sKid]

Hey guys ,

I'm working out of town right now and need some info on my truck but it's sitting at home, so unfortunately I can't find out for myself . I going to order 4.10 gears for my diffs and a shift servo for my tranny but im not exactly sure what I have underneath my truck.

My truck is a 1998 Chev K 1500 5.7L Z71 half ton pick up extended cab short box

I need the specs for my front and rear diffs ( current gear ratio , diff housing size etc , how many bolt it is , etc )
I think it's 3.73 ratio in 8.5" 10 bolt rear diff and a 8.25" front diff......

And what tranny do I have ? I think it's a 4l60e

Can anyone tell me for sure what I have please ??

 

[LoudnLifted88]

yes 4l60 and the front diff is 8.25 and most half ton truck had the 10 bolt rear

 

[That90sKid]

Ok thanks and I'm assuming the rear is a 8.5" hey ?

 

[LoudnLifted88]

Ok thanks and I'm assuming the rear is a 8.5" hey ?

if its a 10 bolt i think so

 

[That90sKid]

Does anyone if I have a open carrier or a posi carrier ? And how many spline it is ? I think it's 30

 

[LoudnLifted88]

Does anyone if I have a open carrier or a posi carrier ? And how many spline it is ? I think it's 30

the only way to know if its a locker is to look at your rpo tag in the glove box or if you have your vin with you, you could look it up online and itll tell ya if it has a locker or not

 

[dirtridinz71]

Trans is a 4L60E and front is a 8.25". Now the rear could either be a 8.5" 10 bolt (30 spline) or 9.5" 14 bolt. No way to tell for sure without the RPO code, VIN or pictures of the truck, there were plenty of ecsb 1500's with the F44 package with the 14 bolt. Same as being able to tell if open, G80 or another aftermarket unit without pulling the cover off.

 

[That90sKid]

Okay so I just found out that I have a 14 bolt rear end which means I have a 9.5" housing and a G80 carrier right ??

 

[LoudnLifted88]

Okay so I just found out that I have a 14 bolt rear end which means I have a 9.5" housing and a G80 carrier right ??

it still could be open you wont know unles you check the rpo tag run your vin online or pull your diff cover

 

[TylerZ281500]

or do a burnout and see if one or both tires spin =)