The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1960 - 1966 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 10-18-2021, 10:19 AM   #1
blacknwhitedog
Registered User
 
Join Date: Mar 2012
Location: Sonoma CA
Posts: 55
Leaf spring conversion

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.
blacknwhitedog is offline   Reply With Quote
Old 10-18-2021, 01:04 PM   #2
350TacoZilla
Registered User
 
Join Date: Sep 2010
Location: Hancock Md
Posts: 385
Re: Leaf spring conversion

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
350TacoZilla is offline   Reply With Quote
Old 10-18-2021, 01:12 PM   #3
blacknwhitedog
Registered User
 
Join Date: Mar 2012
Location: Sonoma CA
Posts: 55
Re: Leaf spring conversion

Quote:
Originally Posted by 350TacoZilla View Post
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.
blacknwhitedog is offline   Reply With Quote
Old 10-18-2021, 02:04 PM   #4
caseyjones
Senior Member
 
Join Date: Nov 2013
Location: Portland, OR
Posts: 506
Re: Leaf spring conversion

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.
caseyjones is offline   Reply With Quote
Old 10-18-2021, 04:37 PM   #5
blacknwhitedog
Registered User
 
Join Date: Mar 2012
Location: Sonoma CA
Posts: 55
Re: Leaf spring conversion

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.

Last edited by blacknwhitedog; 11-26-2021 at 06:01 PM.
blacknwhitedog is offline   Reply With Quote
Old 10-18-2021, 05:43 PM   #6
Billy Stuck
Registered User
 
Join Date: Sep 2020
Location: Grand Rapids, MI
Posts: 3
Re: Leaf spring conversion

Quote:
Originally Posted by blacknwhitedog View Post
...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.
Billy Stuck is offline   Reply With Quote
Old 10-22-2021, 12:42 AM   #7
1971 GMC SHORTY
Senior Member
 
1971 GMC SHORTY's Avatar
 
Join Date: Apr 2009
Location: SAN FERNANDO VALLE SOL CAL
Posts: 1,064
Re: Leaf spring conversion

Quote:
Originally Posted by blacknwhitedog View Post
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
__________________
1966 GMC K25 V6 351E Original Utility Truck
2000 C3500 Hot Rod Utility Truck
2003 ROAD KING 100th 124ci 6 Speed
145CI M/P Pro Street FXR
2002 FXDP
2007 2500HD DURAMAX. DD
Studio Teamsters / Mechanic
Retired GM Master Tech 20 Years
Retired Ford Tech 15 Years
1971 GMC SHORTY is offline   Reply With Quote
Old 10-25-2021, 05:24 PM   #8
blacknwhitedog
Registered User
 
Join Date: Mar 2012
Location: Sonoma CA
Posts: 55
Re: Leaf spring conversion

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.
Attached Images
  
blacknwhitedog is offline   Reply With Quote
Old 10-26-2021, 11:28 PM   #9
Joe Pass
Senior Member

 
Joe Pass's Avatar
 
Join Date: Aug 2013
Location: Windsor, California
Posts: 1,042
Re: Leaf spring conversion

I like to see how this works out....
Joe Pass is offline   Reply With Quote
Old 10-27-2021, 12:42 AM   #10
Warrens69GMC
Registered User
 
Warrens69GMC's Avatar
 
Join Date: Jan 2003
Location: Safford,AZ
Posts: 3,613
Re: Leaf spring conversion

...
Warrens69GMC is offline   Reply With Quote
Old 10-27-2021, 10:11 PM   #11
blacknwhitedog
Registered User
 
Join Date: Mar 2012
Location: Sonoma CA
Posts: 55
Re: Leaf spring conversion

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.
Attached Images
  

Last edited by blacknwhitedog; 10-28-2021 at 09:51 PM.
blacknwhitedog is offline   Reply With Quote
Old 10-27-2021, 10:14 PM   #12
blacknwhitedog
Registered User
 
Join Date: Mar 2012
Location: Sonoma CA
Posts: 55
Re: Leaf spring conversion

Next up is removal of the spring hanger brackets. I cross cut the rivet heads and air chisel the heads off.
Attached Images
  
blacknwhitedog is offline   Reply With Quote
Old 10-27-2021, 10:26 PM   #13
blacknwhitedog
Registered User
 
Join Date: Mar 2012
Location: Sonoma CA
Posts: 55
Re: Leaf spring conversion

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
Attached Images
 
blacknwhitedog is offline   Reply With Quote
Old 10-27-2021, 10:31 PM   #14
blacknwhitedog
Registered User
 
Join Date: Mar 2012
Location: Sonoma CA
Posts: 55
Re: Leaf spring conversion

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.
Attached Images
 
blacknwhitedog is offline   Reply With Quote
Old 10-27-2021, 10:56 PM   #15
Joe Pass
Senior Member

 
Joe Pass's Avatar
 
Join Date: Aug 2013
Location: Windsor, California
Posts: 1,042
Re: Leaf spring conversion

Agree, they are great to deal with
Joe Pass is offline   Reply With Quote
Old 10-28-2021, 06:20 PM   #16
blacknwhitedog
Registered User
 
Join Date: Mar 2012
Location: Sonoma CA
Posts: 55
Re: Leaf spring conversion

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.
Attached Images
 
blacknwhitedog is offline   Reply With Quote
Old 10-28-2021, 07:25 PM   #17
Rickysnickers
Senior Member

 
Join Date: Oct 2014
Location: Eagle, ID
Posts: 2,917
Re: Leaf spring conversion

Flipped it
Attached Images
 
Rickysnickers is offline   Reply With Quote
Old 10-28-2021, 09:37 PM   #18
Joe Pass
Senior Member

 
Joe Pass's Avatar
 
Join Date: Aug 2013
Location: Windsor, California
Posts: 1,042
Re: Leaf spring conversion

taking shape
Joe Pass is offline   Reply With Quote
Old 11-26-2021, 05:59 PM   #19
blacknwhitedog
Registered User
 
Join Date: Mar 2012
Location: Sonoma CA
Posts: 55
Re: Leaf spring conversion 4 bar setup

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.
Attached Images
  
blacknwhitedog is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 05:34 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com