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 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 06-08-2019, 06:27 PM   #1
mister.freeze
Registered User
 
mister.freeze's Avatar
 
Join Date: Dec 2003
Location: Houston, TX
Posts: 617
'71 trailing arm questions

I have a '71 longbed that was made into a trailer. From the get-go, it was bouncy as a trampoline. I put some Monroe Gas Magnum shocks off a Suburban on, thinking the heavier truck had stiffer shocks. They weren't any better. Could have been bad to begin with as the Suburban was just sitting around. My Blazer has a 3/4 ton suspension kit on it, and when I replaced the Pro Comp shocks on it with Bilstien's I warrantied out the Pro Comps and put a new pair on the trailer. Still just a bouncy house on wheels. What gives? The original coil springs are on there, is that the problem? I wouldn't think so. Is it just too light? I wouldn't think that would be the problem either. Thoughts? Thanks in advance.
Attached Images
 
__________________
'72 K5, known as 'the Fox.'
mister.freeze is offline   Reply With Quote
Old 06-08-2019, 07:19 PM   #2
Grumpy old man
Senior Member
 
Grumpy old man's Avatar
 
Join Date: Dec 2013
Location: Gods country East,Tn
Posts: 5,935
Re: '71 trailing arm questions

Does it trail straight ? I would load a few hundred lbs in it as far forward as possible and see how it acts ? Are the tires balanced ? pick a point on each side of the axle and measure to the hitch and see if it measures the same ,Sometime home built trailers can be a little off center and wander
__________________
Grumpy old man is offline   Reply With Quote
Old 06-08-2019, 08:32 PM   #3
mister.freeze
Registered User
 
mister.freeze's Avatar
 
Join Date: Dec 2003
Location: Houston, TX
Posts: 617
Re: '71 trailing arm questions

It pulls and tracks just fine. The problem is when crawling around inside it or loading it. It's like it has no shocks at all!
__________________
'72 K5, known as 'the Fox.'
mister.freeze is offline   Reply With Quote
Old 06-08-2019, 09:34 PM   #4
saxart
Registered User
 
saxart's Avatar
 
Join Date: Aug 2012
Location: St. Croix River Valley, WI
Posts: 658
Re: '71 trailing arm questions

My truck was the same way (coil springs) even with new shocks. It didn't get better until I did the shock relocation kit. Now it's like a modern truck . The relocation kit has the shocks shooting toward the back, rather than the center of the truck. Much better geometry. No more bouncy-bouncy...
__________________
Meet "Old Roy": http://67-72chevytrucks.com/vboard/s...d.php?t=707801
saxart is offline   Reply With Quote
Old 06-10-2019, 11:32 AM   #5
mister.freeze
Registered User
 
mister.freeze's Avatar
 
Join Date: Dec 2003
Location: Houston, TX
Posts: 617
Re: '71 trailing arm questions

surely these things didn't bounce like that new. Is it a spring problem more than a shock problem? Is there a 3/4 ton coil spring?
__________________
'72 K5, known as 'the Fox.'
mister.freeze is offline   Reply With Quote
Old 06-10-2019, 03:29 PM   #6
layinrocker65
Registered User
 
layinrocker65's Avatar
 
Join Date: Jun 2005
Location: California
Posts: 257
Re: '71 trailing arm questions

It’s still a weight problem too. With no added weight, it’s always going to be bouncy
__________________
53 GMC 2.5 ton COE
70 Chevy C10 LWB 350/465(soon to be 6.0/4L80e)
74 Chevy C10 SWB 5.3/4L80e
91 GMC Syclone 370/4L80e PT88 AWD
92 GMC Typhoon 6.0/4L80e twin 65s AWD
07 RCLB Sierra Duramax
15 Chevy SS 6.2/TR6060 LSA blower
layinrocker65 is offline   Reply With Quote
Old 06-10-2019, 04:24 PM   #7
saxart
Registered User
 
saxart's Avatar
 
Join Date: Aug 2012
Location: St. Croix River Valley, WI
Posts: 658
Re: '71 trailing arm questions

Quote:
Originally Posted by mister.freeze View Post
surely these things didn't bounce like that new. Is it a spring problem more than a shock problem? Is there a 3/4 ton coil spring?
Now that you mention it, I did a spring replacement when I did the shock relocation kit, so I don't know if it was the shock relocation or the new springs that fixed it. My original springs were 3/4 ton springs that were horrendously worn out from the owner hauling literally TONS of material in the bed over the years, so it could have been that they were worn out.

I agree with others that it will tow a lot better if you had a couple of hundred pounds in the back of it.
__________________
Meet "Old Roy": http://67-72chevytrucks.com/vboard/s...d.php?t=707801
saxart is offline   Reply With Quote
Old 06-10-2019, 05:54 PM   #8
mister.freeze
Registered User
 
mister.freeze's Avatar
 
Join Date: Dec 2003
Location: Houston, TX
Posts: 617
Re: '71 trailing arm questions

I guess I just had more faith in what shocks can do.
Would it be worthwhile to convert to leaf springs?
Could I do both, like the old squarebody HeavyHalf?
Any stock-height springs laying around?
Attached Images
 
__________________
'72 K5, known as 'the Fox.'

Last edited by mister.freeze; 06-11-2019 at 01:59 PM.
mister.freeze is offline   Reply With Quote
Old 06-11-2019, 01:38 PM   #9
demian5
Registered User
 
demian5's Avatar
 
Join Date: Aug 2016
Location: Lake Forest, CA
Posts: 1,909
Re: '71 trailing arm questions

Quote:
Originally Posted by saxart View Post
My truck was the same way (coil springs) even with new shocks. It didn't get better until I did the shock relocation kit. Now it's like a modern truck . The relocation kit has the shocks shooting toward the back, rather than the center of the truck. Much better geometry. No more bouncy-bouncy...
Hey like 60-62 does from the factory!
__________________
"Work hard, use your vacation days."
1970 C15 GMC Long Bed
1986 C20 Scottsdale (grandpa truck)
1964 Impala SS
1959 Austin Healey 100-6 BN6
Instagram: C10sofOC
demian5 is offline   Reply With Quote
Old 06-12-2019, 07:24 PM   #10
Sparky dave
Registered User
 
Join Date: Nov 2017
Location: Leeds west yorkshire
Posts: 256
Re: '71 trailing arm questions

You think it needs the suspension? If it’s like a pogo stick it’s surely got to be a dampening issue
Sparky dave is offline   Reply With Quote
Old 06-13-2019, 08:24 AM   #11
mister.freeze
Registered User
 
mister.freeze's Avatar
 
Join Date: Dec 2003
Location: Houston, TX
Posts: 617
Re: '71 trailing arm questions

That was my thinking. I guess there's a big difference in when I'm loading and unloading vs going down the road. I'll have to drag it around and have the kids watch it. Maybe its just bouncing on the big tires when empty. I plan to camp in it and they way it rolls around on the suspension is no good. If anybody swapped out some c20 springs to lower theirs I'd be interested...
__________________
'72 K5, known as 'the Fox.'
mister.freeze 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 08:53 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.
Copyright 1997-2013 67-72chevytrucks.com