68 C30 to 85 c30 suspension

[68c30bagged]

Alright guys I'm working on my 68 c30 I got a donor 85 c30 for all front suspension. My true my question is are the c10 and c30 control arms different in 85? Cause if I can run c10 arms I will order some tubulars! Thanks for any info in advance.

[BigBlockBurris]

Your truly better off to swap the whole front crossmember.

[68c30bagged]

Originally Posted by BigBlockBurris

Your truly better off to swap the whole front crossmember.

will the whole crossmember bolt right in? i bought an 85 c30 parts truck so i have front crossmember, control arms, brakes, steering, etc from that truck to use.

[SCOTI]

Originally Posted by 68c30bagged

Alright guys I'm working on my 68 c30 I got a donor 85 c30 for all front suspension. My true my question is are the c10 and c30 control arms different in 85? Cause if I can run c10 arms I will order some tubulars! Thanks for any info in advance.

will the whole crossmember bolt right in? i bought an 85 c30 parts truck so i have front crossmember, control arms, brakes, steering, etc from that truck to use.

C10 & C30 arms are similar but different.

C10 uppers use smaller mounting studs for the shafts & the BJ taper is smaller vs. a C30. Lower arms interchange but the BJ taper could be different (drum brake vs. disc typically are different).

Both upper & lower Squarebody model a-arms have/use different bushings . C10's use car style press-in bushings. C20's & 30's use the HD style threaded bushings like 67-72's.

Yes the entire x-member can be swapped. Things that might change would be the engine/motor mount perches being @ different heights as Squarebody frames were slightly taller. Physically, the x-member will swap right over & might require reaming a couple of the holes.

[Sheepdip]

Just finished one yesterday read this
http://67-72chevytrucks.com/vboard/s...d.php?t=803011

[68c30bagged]

Originally Posted by Sheepdip

Just finished one yesterday read this
http://67-72chevytrucks.com/vboard/s...d.php?t=803011

Thanks for the info definitely will help! Just a quick question if i swap the cross memeber to an 85 and put power steering from 85 would i use the 85 idler and pitman or the 68?

[Sheepdip]

Originally Posted by 68c30bagged

Thanks for the info definitely will help! Just a quick question if i swap the cross memeber to an 85 and put power steering from 85 would i use the 85 idler and pitman or the 68?

I can only quote on using your existing 68 steering cross link which is the same as my 70, here was my experience.

I chose to keep the exiting cross member because I saw no reason to change it, to me that was a whole bunch of unnecessary work everything will bolt right up to your existing cross member.

I measured the 86 steering link and found it to be 1-1/4" narrower or shorter where the Pitman Arm and Idler Arm mount to the outer tapers so this will automatically throw your steering geometry off, the idler arm for the 86 taper hole where it mounts is also 1 size smaller taper than the 68.

The inner tapers where the tie-rods mount are 1/4" shorter/closer together
Bottom line is if you keep your 68 cross member you cannot use the 86 steering link, you must reuse your 68.

I did not have the 86 donor truck to measure why the difference but I suspect its in where the steering box and idler arm mounts, I don't know and do not want to speculate. I can tell you that what I used lined right up to spec's at the alignment shop.

Sorry I couldn't answer directly on what you're wanting to do.

[clay68c10]

I would ALL the 85 steering parts, including the box. The hydraulic line ends are different, so grab the 85 pump pressure outlet fitting so you can use off the shelf lines for the 85. You also gain a bit quicker ratio with the newer box.

[littlehopper]

following