Leaf spring conversion

[blacknwhitedog]

Ive never been happy with the leaf spring setup on my 64 gmc. I want to convert to the trailing arm setup. Other than trailing arms, springs and shock mounts, pan hard bar, plus welding on new spring perches to the axle, what else is different? Upper coil spring buckets mount to the frame? Anyone done this? Also looking at the cpp tubular trailing arm kit, but prefer using factory style arms.

[350TacoZilla]

I cant help directly but another member on here just did the switch to trailing arms. He didn't do a step by step but would be a quick guide.

http://67-72chevytrucks.com/vboard/s...=823008&page=2

[blacknwhitedog]

Originally Posted by 350TacoZilla

I cant help directly but another member on here just did the switch to trailing arms. He didn't do a step by step but would be a quick guide.

http://67-72chevytrucks.com/vboard/s...=823008&page=2

Thanks...I saw that on here earlier. It looks like the spring cups bolt directly to the frame and the the trailing arms. I also need to think about shock mounts, and panhard bar.

[caseyjones]

My gmc didn’t have the crossmember that spans the frame where the upper coil mounts, you’ll want that and the frame-side panhard bar mount. You’ll need the trailing arm brackets that mount to the forward crossmember too.

[blacknwhitedog]

Thanks everyone for your help. I've decided to go with the no-limit engineering
4 bar setup, as it requires less welding and allows me to keep the exhaust system I already have.

Hope to get this going in the next couple of months. I'll try to remember to post pics when I do.

[Billy Stuck]

Originally Posted by blacknwhitedog

...I've decided to go with the no-limit engineering 4 bar setup...I'll try to remember to post pics when I do.

Yes, please do. leaning towards doing the same with my 3/4 ton misfit.

[1971 GMC SHORTY]

Originally Posted by blacknwhitedog

Thanks everyone for your help. I've decided to go with the no-limit engineering
4 bar setup, as it requires the less welding and allows me to keep the exhaust system I already have.

Hope to get this going in the next couple of months. I'll try to remember to post pics when I do.

I Have Everything To put back Factory Parts

[blacknwhitedog]

Well, here we go. The 4 bar kit is arriving today or tomorrow. Depends upon fedex…First order of business is to level the frame side to side and front to back.
Make sure the bed is off the truck and the jack stands are in front of the engine. Had an oh **** moment when I began to remove the rear axle with stands under the front of the cab. It was balancing on the two stands because of the front heavy nature of these trucks.

Second important piece of the puzzle is to accurately locate the axle centerline on the frame. Short bed centerline is 33 1/2 from the back edge of the frame.

More to follow on the weekend.

[Joe Pass]

I like to see how this works out....

[Warrens69GMC]

...

[blacknwhitedog]

Got some garage time today. First order of business is assembling the bars. It’s a good idea to run a tap through the threads prior to assembly. Use some anti gall lubricant when assembling. Center to center length should be 30 1/4 center to center. Make all four the same length and snug down the locknuts.

[blacknwhitedog]

Next up is removal of the spring hanger brackets. I cross cut the rivet heads and air chisel the heads off.

[blacknwhitedog]

Gmc trucks have some quirky extras that make modifications interesting. One each side of the spring hangers are raised areas to strengthen the frame area. Great idea but when your 4 bar brackets are supposed to sit flat against the frame….it’s a problem. A quick call to Rob at nolimit engineering confirmed what I needed to do…cut off the forward part of the bracket so it lays flat. I’ll be welding these on after everything is lined up, but if you needed to you could add some forward mounting holes to make up for the two you had to cut off. Below you can see the raised portion of the frame that interferes with the front part of the bracket. Tried to turn the photo..but no luck

[blacknwhitedog]

By the end of the day, I had this….can’t say enough good things about the nolimit kit. Reasonably priced and well engineered, plus great tech support.

[Joe Pass]

Agree, they are great to deal with

[blacknwhitedog]

Scored some more garage time today. Removed all the brackets from the axle and prepped it for the new 4 link brackets. Here’s what I have so far. 4 bar brackets are tacked up. Mocking up the the panhard bar bracket and shock mounts.

[Rickysnickers]

Flipped it

[Joe Pass]

taking shape

[blacknwhitedog]

Haven’t had much of a chance to get any garage time but I did get one c-notch installed. These are weld in units from Speedway motors. I’ve never been a fan of the current bolt in notches as it removes too much frame. These happen to be 2” deep with a small urethane bump stop. The frame will get boxed in this area, along with some 4” rectangular tubing crossbars.