Picking up a Suburban for a donor for my K5

[93FatBottom]

I scored a deal on an 86 K20 Suburban. Running driving 350/TH400/NP208/10b/14b. Its beat to hell body/interior wise, leafs are saggy, real rusty, etc. But she runs great, no funny noises, good oil pressure, half hour test drive 190 degree temps, 4x4 worked great hi and lo. I'm going to pick it up on a Friday and drive her home, then swap my 10b/12b on the K5 to the Suburban and the 10b/14b to the K5, pull the motor, trans, tcase sunday morning, and my scrap guy already penciled me in to pick it up Sunday evening. I'm excited to finally get the damn thing on the road! As soon as the swaps done, the following month gonna order the lift and Thanksgiving weekend shes gonna make her debut out in Johnson Valley, CA! (If all goes according to plan, which in my world, it never seems to )

Questions: I'm getting conflicting info on if the 3/4 ton axles will fit underneath the truck with no lift. The front is a 10 bolt 6 lug, so swapping to 8 lug 10 bolt shouldn't make much of a difference, right? I hear that the 14 bolt semi floater rear wont fit with the gas tank installed, but I wont have the gas tank installed until after the lift kit (currently running her with a gas can and fuel lines up front). But to be sure, can anyone confirm?

Also, will the K5 stock steering and brake lines hook up to the 3/4 ton axles, and if not, what needs to be changed to make the swap quick and easy? I've been looking for a TH400/NP208 driveshaft but no luck, so I'm thinking i'll end up at Wenco for a custom shaft, so I'm not concerned with that at the moment.

Do I need new spring plates to attach the 3/4 axles to my stock K5 leaf springs? And vice versa for the 1/2 ton axles under the Suburban? I've been told that I can just swap everything between the trucks, but I was then told that the Suburban rear leaf springs wont fit the K5 (52" vs 56"?) and that it might give me trouble.

My other question is about the transfer case shifter. I currently have an NP203. Do I need to cut the hole in the trans hump to fit the NP208 shifter? Or will it fit? This question isn't too important, the motor/trans/tcase swap wont come until later September/early October.

I'm just trying to get all my ducks in a row, because I only have that weekend to do the axle swap work, and I need the Sub gone that Sunday night.

Any other advice would be much appreciated!

Thanks guys!

[93FatBottom]

OH! One more thing. I need to figure out how hook up the E-brake. I saw a video showing you could remove the cable from the 12 bolt rear and install in the 14 bolt, but it wasn't exactly clear on how to do it. If anyone has info on this to elaborate, it would be much appreciated as well!

[68Timber]

If you're going to lift it, maybe consider holding off on the axle swap until you have the new springs. I read somewhere that U-bolts were shouldn't be reused. Not that I haven't done it before and probably will again, but if you're going to the trouble of swapping the axles and springs, I'd at least use new U-bolts for final assembly. Honestly I'm not versed in all the different versions of spring lengths but you'll be able to pull a tape on it shortly and know for sure. The rear diff on the 14-bolt is bigger, but I can't imagine it being so big that it'd hit the tank without a lift. And I don't mean to be a wet blanket, but a replacement gas tank should come before bigger axles and a lift. Right now you're running the risk of burning it down and maybe hurting yourself or someone else in the process. Not sure on the shifters. I've never done this swap but it's so common I'm sure someone who has will chime in.

[93FatBottom]

Originally Posted by BRUISER

If you're going to lift it, maybe consider holding off on the axle swap until you have the new springs. I read somewhere that U-bolts were shouldn't be reused. Not that I haven't done it before and probably will again, but if you're going to the trouble of swapping the axles and springs, I'd at least use new U-bolts for final assembly. Honestly I'm not versed in all the different versions of spring lengths but you'll be able to pull a tape on it shortly and know for sure. The rear diff on the 14-bolt is bigger, but I can't imagine it being so big that it'd hit the tank without a lift. And I don't mean to be a wet blanket, but a replacement gas tank should come before bigger axles and a lift. Right now you're running the risk of burning it down and maybe hurting yourself or someone else in the process. Not sure on the shifters. I've never done this swap but it's so common I'm sure someone who has will chime in.

Bruiser, I appreciate your response. This truck is not a daily driver. The engine in it right now has a bad oil pump and a wicked lifter knock. It hasn't been registered since 2004, and up until I pulled it out of the spot it was in, hadn't moved since 2005. The truck is a project. I'm strictly doing things as I am able to do them. The Suburban is strictly for parts, but I gotta get the axles swapped in order for the K5 to be on the new axles and the Suburban to be on rollers to get towed out of here. I'm going to reuse the ubolts strictly to get the Suburban to the scrap yard and the K5 to be movable between my driveway and the street. I plan on a new Tuff Country lift in October, complete with new U-bolts.

The gas tank is mashed up and rusted. I actually pulled it out tonight. Lots of rat **** and black widow webs up there too!

[68Timber]

10-4, somehow I got the impression that you were going to drive it some but rereading your post I can see that's not the case. Chalk it up to lack of coffee. This swap has been done by everyone and their brother it seems, except me and you. I can't imagine it's not all bolt-in. As far as the driveshaft, can't you shorten it and reuse it? I've had a NP203 truck before and I've got a NP208 truck now, later today I'll get under it and see what I can tell.

[93FatBottom]

Of course not, I'm not 18 anymore haha. Upon further looking around, I came across what appears to be a tech training vehicle. It shows them tearing the brakes apart on a 5 lug 10 bolt, but from what I can gather, its all the same stuff. Apparently, the cable connects to the brake shoes the same way regardless, but with old vs new parking brake styles, the cable either clips into the backing plate, or its bolted to the backing plate. I'm not so sure which is which. I neglected to check the last time I was at the yard where the Sub is, and I wont be back again until I go to pick it up in a few weeks... I read somewhere that I need to retain the backing plates, so now I'm confused. In order to connect my 12 bolt parking brake cables to my 14 bolt, do I need to reuse the 12 bolt backing plates as well?

[Ski-me]

I installed a 91' 3/4 suburban 14SF axle under my K5 without any issues. Gas tank clearance is just fine. I went a bit further and swapped the 6 lug SF brakes, axle shafts and drums from a later model 97 over to the 91' (originally 8 lug). I then pulled my front 6 lug brakes, rotors and axle shafts and installed into the 91' 3/4 front axle. That way I got 3/4 strength (in back really), but also gear change to 4.10's....and keeping the 6 lugs so no new wheels. Spring perches, shocks all bolted up directly without any issues.

[motornut]

this is on my 78 Jimmy list of plans too,gona be donor for me too