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 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 05-22-2011, 11:07 AM   #1
Conundrum
Registered User
 
Conundrum's Avatar
 
Join Date: Oct 2008
Location: Parsons, KS
Posts: 652
Crossmember Trouble.....

I ran into a problem while trying to put my sectioned crossmember in (from a 86 suburban), it is give or take a little a 1/2" narrower at the upper a-arm towers than the original (a 74 pickup) both half tons.
Did the frame width, maybe even the track width change at some point during the long production run of these trucks?
Or is there a difference between the suburban and pickup crossmembers that I wasn't aware of?

Will it be ok to go ahead and get this one on here, or should I just section the original?
__________________
74 GMC SWB Project "Sin-thia" Static Dropped 8"f/10"r
http://67-72chevytrucks.com/vboard/s...d.php?t=460030


97 GMC reg cab short bed, 4.3V6 / 5spd, daily driver
220,000 miles, all stock for now

Last edited by Conundrum; 05-22-2011 at 11:17 AM.
Conundrum is offline   Reply With Quote
Old 05-22-2011, 11:40 AM   #2
N2TRUX
Happy to be here
 
N2TRUX's Avatar
 
Join Date: Mar 2000
Location: Cypress, TX
Posts: 39,023
Re: Crossmember Trouble.....

They should all be the same from 73-87. Is it possible you changed the dimensions while sectioning the crossmember?
__________________
Follow me on Facebook and Instagram @N2trux.com

Articles-

"Jake" the 84 to 74 crewcab

"Elwood" the77_Remix

85 GMC Sierra "Scarlett"

"Refining Sierra"
N2TRUX is offline   Reply With Quote
Old 05-22-2011, 11:47 AM   #3
Conundrum
Registered User
 
Conundrum's Avatar
 
Join Date: Oct 2008
Location: Parsons, KS
Posts: 652
Re: Crossmember Trouble.....

I had thought about that, so I grabbed the support that I made before I did any cutting and set it up to the 74 crossmember and it fell 1/2" short as well. I built the support off the crossmember, so I think it should have stayed the same. And the main part of the support was made out of some 1/2" steel I had sitting around so I don't think it bent during the process. This has me stumped and dumbfounded!
__________________
74 GMC SWB Project "Sin-thia" Static Dropped 8"f/10"r
http://67-72chevytrucks.com/vboard/s...d.php?t=460030


97 GMC reg cab short bed, 4.3V6 / 5spd, daily driver
220,000 miles, all stock for now
Conundrum is offline   Reply With Quote
Old 05-22-2011, 11:56 AM   #4
N2TRUX
Happy to be here
 
N2TRUX's Avatar
 
Join Date: Mar 2000
Location: Cypress, TX
Posts: 39,023
Re: Crossmember Trouble.....

Anything is possible, but the crossmembers are all "supposed" to be the same. There have been tons of crossmember swaps done on 67-72 using 73-87 crossmembers, and I have never heard of anyone having an issue of the type.

Is it possible to tweak the crossmember to make it fit?
__________________
Follow me on Facebook and Instagram @N2trux.com

Articles-

"Jake" the 84 to 74 crewcab

"Elwood" the77_Remix

85 GMC Sierra "Scarlett"

"Refining Sierra"
N2TRUX is offline   Reply With Quote
Old 05-22-2011, 12:03 PM   #5
Conundrum
Registered User
 
Conundrum's Avatar
 
Join Date: Oct 2008
Location: Parsons, KS
Posts: 652
Re: Crossmember Trouble.....

My dad has a portapower(?), I could possibly use that and try to spread it enough to fit.

I'll snap a couple pics soon, of my current situation....
__________________
74 GMC SWB Project "Sin-thia" Static Dropped 8"f/10"r
http://67-72chevytrucks.com/vboard/s...d.php?t=460030


97 GMC reg cab short bed, 4.3V6 / 5spd, daily driver
220,000 miles, all stock for now
Conundrum is offline   Reply With Quote
Old 05-22-2011, 01:53 PM   #6
Conundrum
Registered User
 
Conundrum's Avatar
 
Join Date: Oct 2008
Location: Parsons, KS
Posts: 652
Re: Crossmember Trouble.....




So I measured the stock crossmember and another crossmember that i've got lying around from a 74 3/4 ton pickup, I measured the same points on each, a flat place on the front top and bottom inside of the UCA mount stand and here's what I got.....
..............Top.........Bottom......Center-Center of the front bottom bolt holes
Stock....29-7/16".....29-3/8"......26-3/8"
3/4 T....29-3/16".....29-1/4"......26-3/8"
Chppd....28-3/4"....28-15/16".....26" (these are slotted)

My dads got a portapower(?) so we may try and see if it will spread and work, or is this one lost? If so i'll try it again, and hopefully get it right this time around.
__________________
74 GMC SWB Project "Sin-thia" Static Dropped 8"f/10"r
http://67-72chevytrucks.com/vboard/s...d.php?t=460030


97 GMC reg cab short bed, 4.3V6 / 5spd, daily driver
220,000 miles, all stock for now
Conundrum is offline   Reply With Quote
Old 05-25-2011, 08:40 PM   #7
Conundrum
Registered User
 
Conundrum's Avatar
 
Join Date: Oct 2008
Location: Parsons, KS
Posts: 652
Re: Crossmember Trouble.....

Well it worked!


__________________
74 GMC SWB Project "Sin-thia" Static Dropped 8"f/10"r
http://67-72chevytrucks.com/vboard/s...d.php?t=460030


97 GMC reg cab short bed, 4.3V6 / 5spd, daily driver
220,000 miles, all stock for now
Conundrum is offline   Reply With Quote
Old 05-25-2011, 08:44 PM   #8
PRattenbury
Senior Member
 
Join Date: Feb 2010
Location: Maumelle, AR
Posts: 478
Re: Crossmember Trouble.....

Good work!
PRattenbury is offline   Reply With Quote
Old 05-25-2011, 08:49 PM   #9
Pop's C-10
Registered User
 
Pop's C-10's Avatar
 
Join Date: Jul 2010
Location: memphis
Posts: 2,537
Re: Crossmember Trouble.....

By choice or by force..
__________________
1981 C-10 (Pop's)
1978 Camaro
2006 Lacrosse
Pop's C-10 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 05:29 PM.


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