8" Lift & 3/4 Ton Axel swap - Help Needed!

[Ryan Flowers]

Fellow gear heads,

I need help with the following:

I am going to put an 8" lift on the 90 Suburban. While I am at it I want to go ahead and drop a pair of GMC 3/4 Ton axles under it. Can anyone tell me if this is a swap and bolt project? I know I will have to have new drive shafts made but are there any hidden things I should know about, like brake cables and hoses not matching up or spring perches needing to be relocated. I will also be doing a cross over steering (thanks Pont for that recomendation). As soon as she is complete I will be posting pics. Any and all info would be GREATLY appreciated.

Thanks,

[NAPCO ken]

I am running 8" lift on my '90 Suburban, also with 3/4 ton axles (actually since then, I've installed a 1 ton Dana 60 front end). You will need longer brake lines. The exhaust crossover that goes underneath the front driveshaft will have to be modified to allow clearance for the driveshaft. The rear driveshaft I did not modify, except to get a conversion u-joint to go the the 14 bolt rear end. Since I installed the Dana 60 front end, I did noot find it necessary to lengthen the front driveshaft, as the 60s pinion snout sticks out a bit further than it's 3/4 ton counterpart. Crossover steering is the hot ticket. I have it on two of my vehicles and cannot imagine steering a lifted truck without it! Good luck.

[Pont]

Your welcome Ryan, glad to help anyway I can. Like NAPCO Ken said, can't imagine driving a lifted rig without it.

Good luck on the project, looking forward to seeing pics........

[Ryan Flowers]

NAPCO Ken,

Thanks for the info. Where did you get the U-Joint Conversion. I have asked around and no one seems to have a clue about them. Will I have to lengthen the front drive shaft? I would think I would.


Pont,

When I had talked to you about the cross over steering last time I was going with the 1/2 Ton axles but I decided to beef it up a bit. I guess I will have to give Parts Mike a call and order the kit for the 3/4 Ton.

I will post pictures as I complete each step. Thanks for all the help guys.

[NAPCO ken]

Ryan, you will probably have to lengthen your front shaft. As for the conversion U-joint, Parts Mike should be able to help you out there. I got mine from a local driveshaft shop, but that was 9 years ago when I did the change over to the bigger axles!

[Beast388]

The conversion u-joint to go from a 10 bolt to 14 bolt is Napa P/N 447.

[Ryan Flowers]

Beast388,

Thanks for the Napa part number.

NAPCO Ken or Pont,

Do either of you guys have any pics of a 3/4 hub with out center caps on an aluminum wheel. I didn't order any center caps because I thought it would look better with the rear hubs sticking out like the front ones. But I would like to look at both.

I still need to call parts mike for the cross over kit. I have had the axles and the Heavy Duty bumper for a few months now but all the other parts arrived today. I recieved:

5 each 36x14.50x16.50 SS/TSL Radials mounted on 16.50x12 Eagle 589's

8" Springs front & rear along with all the accessories, brake lines, shocks and so on.

I will try to post a picture of the bumper tomorrow. I will aslo keep everyone posted of steps along the way.

Remember: "If it doesn't say Chevorlet/GMC on the grill, then you bought a peice of sh@t".

[NAPCO ken]

Sorry, I don't have any pictures of the hub stickin through, although on all 3 of my 3/4 and one ton 4x4s with Weld Racing aluminum wheels I left the center caps off to let the hub stick through...I think it looks WAY better that way. Besides if you ever have to pull the axle shaft for some reason, you don't have to pull the entire wheel off to get the center cap off.