Going from leafs to coils, should I?

[Mad Viking]

I have a 71' 3/4 ton that has leaf springs. I found on Craigslist a deal for trailing arms, crossmember, coils and misc parts for $150. This came out of a 71' 3/4 ton. First, is this a good deal for the parts to convert to trailing arms/coils? Second, is the conversion difficult to do, kind of put the crossmember in right and you're good to go or is there more modification than that. Any advice will be helpful.

[Jacfourteen]

To do the swap you will have to either weld the trailing arm perches on your rear or swap to a coil rear.

[lofly'a]

Jacfourteen is on the money with the spring perches needing to be moved. you will also need to remove the upper shock crossmember and use a trailing arm shock crossmember unless you go with a custom shock setup. if you use the stock setup you'll also need the lower shock mounts also which bolt to the bottom of the rearend u-bolts.
i'm not sure about 3/4 ton gmc's, but my 71 1/2 ton already had the trailing arm crossmember there from the factory. i just installed the end links to the crossmember and bolted the trailing arms up to them. here is a list of all the parts you will need for a "factory correct" conversion:

1. coil spring rearend
2. coils (2)
3. trailing arms (2)
4. u bolts (2)
5. t-arm crossmember if not already installed
6. upper shock crossmember
7. lower shock mounts (2)
8. trailing arm and trailing arm frame bracket

hope i did'nt forget anything

[Jacfourteen]

Oh, and if you want to keep your rear you will have to figure out how to mount the panhard bar as there is no mount on a leaf rear.

[eagleuh1]

My 68 3/4 has the crossmember with rivet holes for trailing arm mounts. I've thought about doing this also. Maybe in the future. Are 3/4 trailing arms different from 1/2 ton. How bout long bed vs short bed trailing arms? Goood luck.

[Ackattack]

I believe the 3/4 ton arms have a little extra reinforcement, but are interchangeable. Same arms for LWB vs SWB

I'm converting my 3/4ton leaf to 1/2ton coil here shortly too.

[Mad Viking]

I will be taking a good look at the rear suspension of my truck ASAP. I have some pictures of it that I'll look at tonight and maybe those will give me the information I need otherwise and I need to go look at it Monday. I'm just unlucky that I don't have the truck at my house right now. Not enough room.

[ERASER5]

Use an ECE panhard bar. It does not mount to the diff, it mounts to the trailing arm.

[68GMCCustom]

I'm swapping my GMC to coils...cutting all the rivets is probably the hardest part!

[Jacfourteen]

Originally Posted by ERASER5

Use an ECE panhard bar. It does not mount to the diff, it mounts to the trailing arm.

Yeah I thought of that this morning, but you beat me to it. It also helps to correct geometry if/when you drop it.

[Mad Viking]

This is very useful information. Thanks for passing it along.