1500 lift spindles on 3500 hub assembly

[Nuts4camaros68]

I have all parts to swap to 3500 on front end of my 88 1500 ext cab long bed. I have converted rear to 8 lug 14 bolt know I'm converting front end. I have 3500 upper a arm. Stock spindle and hubs. But want to keep my 4 " lift. so I'm not sure if I can use the 1500 4" lift spindles or will be needing to buy the 3500s lift spindle now too. Or is the upper ball joint and spindle not compatible.

 

[Schurkey]

Gonna make a HUGE difference if this is a 2WD or 4WD.

If this is a 4WD, the 3500 upper arms are not going to fit the frame. The 8-lug control arms are wider.

You must be registered for see images attach

I have no idea about 2WD.

I'm thinking--but not sure--that the 5- or 6-lug ball joints will not fit the 8-lug steering knuckle.

I bet you have JN5 brakes. You'll need a different master cylinder to go with the 3500 calipers.

Be sure to aim the headlights afterward.

 

[Nuts4camaros68]

Gonna make a HUGE difference if this is a 2WD or 4WD.

If this is a 4WD, the 3500 upper arms are not going to fit the frame. The 8-lug control arms are wider.

You must be registered for see images attach

I have no idea about 2WD.

I'm thinking--but not sure--that the 5- or 6-lug ball joints will not fit the 8-lug steering knuckle.

I bet you have JN5 brakes. You'll need a different master cylinder to go with the 3500 calipers.

Be sure to aim the headlights afterward.

Wow was not aware there's a differnce in 4wd. A arms. I got the all the 3500 parts off a 2wd C3500. Mine is a C1500. I got blocks and the add a leaf to install. Only going to run the block if it's noticeably higher in the front once falls installed. No squatting here Thanks lmao. Yea I'm not sure about the ball joint and spindle knuckle working together. Why I came here. To ask. Don't want to buy a spindle if there compatible. And don't want to find out during tear down and assembly weekend. Then have to have it sit tore down till I order the 3500 spindles . I'm gonna cross reference stock spindle part #s see if they match. And if they have them in stock I may go measure side by side as well.

 

[Nuts4camaros68]

W

Wow was not aware there's a differnce in 4wd. A arms. I got the all the 3500 parts off a 2wd C3500. Mine is a C1500. I got blocks and the add a leaf to install. Only going to run the block if it's noticeably higher in the front once falls installed. No squatting here Thanks lmao. Yea I'm not sure about the ball joint and spindle knuckle working together. Why I came here. To ask. Don't want to buy a spindle if there compatible. And don't want to find out during tear down and assembly weekend. Then have to have it sit tore down till I order the 3500 spindles . I'm gonna cross reference stock spindle part #s see if they match. And if they have them in stock I may go measure side by side as well.

ent out and measured my a arms. And the 3500. They're identical in width. From outside bushing to bushing is 15" on both and the actual a arm is 13 1/2" on 1500 and 3500. So that will fit no issues.

 

[Schurkey]

So that will fit no issues.

Fits the frame. Still some question on whether the ball joint stud fits the steering knuckle.

 

[1998_K1500_Sub]

Hasn't this been covered before, and found to be challenging (impractically difficult) on account of the taller frame of the 2500/3500s as compared to the 1500s... which translates into incompatible mounting locations for the upper control arms vs. the 1500 frame and/or impractical suspension geometries when bolted together?

Evidently OP wants an 8-lug front on account of his (now) 8-lug rear.

Somebody on GMT400 can speak to this with more authority, I'm sure.

 

[1998_K1500_Sub]

can use the 1500 4" lift spindles or will be needing to buy the 3500s lift spindle

If you could fit an 8-lug hub on a 1500 spindle, you wouldn't need to do anything more since that would satisfy your objective; you wouldn't need to fuss with control arms or anything else.

AFAIK it's not possible, one obvious reason being that the caliper mounting bosses aren't properly located to accommodate the larger 8-lug rotor. There are probably other reasons TBD.

 

[someotherguy]

Upper control arms swap between C1500's and 8 lug C2500/C3500 (6 lug C2500 is the same stamped arm a C1500 comes with; the 8 lug trucks get forged.) The lowers are identical across all 3.

8 lug upper control arms use a different ball joint and it won't fit the lighter spindles. There's a few ways you can go about this. Re-drill the 8 lug upper control arms for C1500 ball joint pattern (I think 2 of the holes are off, not sure) or carefully ream the C1500 spindle for the 8 lug truck's ball joint stud.

*If you weren't trying to retain your C1500 lift spindles, I'd say use the 8 lug truck spindles, brakes, etc..

Richard

 

[1998_K1500_Sub]

Upper control arms swap between C1500's and 8 lug C2500/C3500 (6 lug C2500 is the same stamped arm a C1500 comes with; the 8 lug trucks get forged.) The lowers are identical across all 3.

No caster / camber / tie rod / bump steer / handling concerns?

I assume "not", because you didn't mention any, but I'll ask anyway.

 

[someotherguy]

No caster / camber / tie rod / bump steer / handling concerns?

I assume "not", because you didn't mention any, but I'll ask anyway.

It appears to be all the same geometry, just stronger parts, at least on the uppers - forged vs. stamped, and the larger ball joint stud and flange.

Richard