Well, it seems my daily driver 06 Silverado's rear end is giving up the goat after 135K hard miles running 33" MTs since day one. I'm thinking since I tow and it's got 3.42s I would pick up a 9.5" rear hybrid axle from either the V-Max truck or 2wd SS. Other the then GMT-900 trucks do any come with discs in the rear or just drums?

Also, will a GMT-900 9.5" bolt into the GMT-800 platform? I know I'll need to swap out the u joint, hook up brakes and parking brake cable is there anything else I should do?

explain wtf a 900-800 truck is.

explain wtf a 900-800 truck is.

http://en.wikipedia.org/wiki/GM_GMT_platform

explain wtf a 900-800 truck is.

GMT800 is the platform that runs from 99 to 06/07

GMT900 is the platform that runs from 07NNBS to current.

Wouldn't it be easier to say the year and weight rating of truck?

like "1980 GMC 1/2 ton" ?

Cause who the fuck wants to read that whole wiki article to just understand the question?

GMT800 is the platform that runs from 99 to 06/07

GMT900 is the platform that runs from 07NNBS to current.


way to precise bro

way to precise bro

Never....:flipoff2: Anyone help a fellow out?

Well, it seems my daily driver 06 Silverado's rear end is giving up the goat after 135K hard miles running 33" MTs since day one. I'm thinking since I tow and it's got 3.42s I would pick up a 9.5" rear hybrid axle from either the V-Max truck or 2wd SS. Other the then GMT-900 trucks do any come with discs in the rear or just drums?

Also, will a GMT-900 9.5" bolt into the GMT-800 platform? I know I'll need to swap out the u joint, hook up brakes and parking brake cable is there anything else I should do?

AFAIK, the perch width of the axles from 99 and on has been 49" so any axle from a 99+ truck should bolt in. There is no hybrid 9.5 14SF.

A cheaper source of these axles would be 88-98 half ton Z71s or 3/4 ton 6 lug vans from the same year range. These axles will have drums, but it takes little effort to swap to disks. You would also need to relocate the perches.

BTW, for 33" tires you would have done better with 4.10 gears.

All the GMT800 6 lug 14SF are Disk brakes. The come with 3.73's or 4:10's. And usually the G80. I don't think the GMT900 truck rear end will fit directly. The 99-06 and 07 classic will bolt right in though.

I would also upgrade to hydroboost. Pretty easy using stock parts and will help with braking.


The GMT800/900 is GM's platform designation fot the fullsize trucks and SUV's Easy to say the platform than NBS or NNBS or other shit like that!

AFAIK, the perch width of the axles from 99 and on has been 49" so any axle from a 99+ truck should bolt in. There is no hybrid 9.5 14SF.

A cheaper source of these axles would be 88-98 half ton Z71s or 3/4 ton 6 lug vans from the same year range. These axles will have drums, but it takes little effort to swap to disks. You would also need to relocate the perches.

BTW, for 33" tires you would have done better with 4.10 gears.

Yes, I would agree w/ the 4.10s, I didn't order this truck I got it off the lot for a deal new.

I am going with 4.10s this time around because with any trailer weight I'm stuck in 3rd gear.

I'm going by what GM calls the axle a "hybrid".


All the GMT800 6 lug 14SF are Disk brakes. The come with 3.73's or 4:10's. And usually the G80. I don't think the GMT900 truck rear end will fit directly. The 99-06 and 07 classic will bolt right in though.

I would also upgrade to hydroboost. Pretty easy using stock parts and will help with braking.


The GMT800/900 is GM's platform designation fot the fullsize trucks and SUV's Easy to say the platform than NBS or NNBS or other shit like that!

I'd love to I'm just not sure I can pull it off. I'm nervous about swapping out the master on my DD for something that wasn't OE. At one time I had a complete parts list for the swap but I don't know if I have it now. The mounting on the firewall is what scares me.

I'd love to I'm just not sure I can pull it off. I'm nervous about swapping out the master on my DD for something that wasn't OE. At one time I had a complete parts list for the swap but I don't know if I have it now. The mounting on the firewall is what scares me.Pretty easy read these. Uses GM MC and parts.

http://performancetrucks.net/forums/showthread.php?t=441147&highlight=hydroboost

http://performancetrucks.net/forums/showthread.php?t=417445

Should hep you decide.

Also you will need to swap your front gears as well as tune the ECM for for the 4.10's.

Pretty easy read these. Uses GM MC and parts.

http://performancetrucks.net/forums/showthread.php?t=441147&highlight=hydroboost

http://performancetrucks.net/forums/showthread.php?t=417445

Should hep you decide.

Also you will need to swap your front gears as well as tune the ECM for for the 4.10's.

Yes, I'll do the front case when I reseal it, I'm losing fluid from the front now, not bad but you can see it.

I've got HP tuners already so the gears will be easy.

I'll check out the links and see if I feel comfortable doing it.

i swapped a semi float 14 bolt into my 02 silverado 4x4. i got a 4.8 with a 5 speed stick and i blew up 2 10 bolts under warrenty til i had enough. mine came out of a 94 half ton z71 and it had a gov bomb in it. picked it up at the pick n pull for 140 bucks. took a bit of work but it worked out nice. i moved the mount on the axle out for the brake backing plate and my stock brakes bolted right up from there. had to move the spring mounts out a bit and shocks too.basically gota strip the axle and relocate all the mounts. got a cross joint from napa auto parts and the driveline went right in. took me and a buddy two weekends to do. if you have the skill its cheaper that way to.

wrecking yards around here wanted 1400 for one outa a 99 here that would bolt in.and i searched a bit and from what i read after 99 all the 1500s that came with 14 bolt semi were the hds and they were 8 lug. i only found one like that.

oh and dont use the 3/4 ton 6 lugs unless u wanna use wheel spacers. learned that the hard way. its 3 inches shorter width didnt catch that til i went to put my tires on and they hit the springs. id dont know why they did that to those axles but i researched it here and i wasnt the only one that happened to

and all new bearings,seals, brakes and have the r n p checked or replace but thats obvious.

cost me bout 600 total to get mine done but my carrier was in great shape.
most of the ones i found were 3.73 gears too. some 8 lugs were 4.10. never found a 14 bolt with 3.42s though jist the 10 bolts

I think I have one a little different...

2000 GMC 2wd 2500(non-HD) with an 8 lug 14SF, disc brakes. Would my potential 6 lug conversion be as easy as swapping the axles and rotors?

I think I have one a little different...

2000 GMC 2wd 2500(non-HD) with an 8 lug 14SF, disc brakes. Would my potential 6 lug conversion be as easy as swapping the axles and rotors?

Does anyone know?

oh and dont use the 3/4 ton 6 lugs unless u wanna use wheel spacers. learned that the hard way. its 3 inches shorter width didnt catch that til i went to put my tires on and they hit the springs. id dont know why they did that to those axles but i researched it here and i wasnt the only one that happened to


Old post I know, but that axle was out of a 2wd truck; they had a narrower track width (65") than the 4wd (68.5" IIRC).

Does anyone know?

I know that the axles can be swapped over. Not sure if the caliper is spaced from the WMS the same difference as the lighter duty versions, but I don't see why it wouldn't be.