swapping out a 6 lug to a 5 lug, what all do i need to change?please hurry - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Nate003 · 02-14-2004, 03:18 PM

Hi everyone, I am about to go take off the front susp. off of a 72 1/2 ton 5 lug disc and put it on a 67 1/2 ton 6 lug drum front end, I'm curious as to whether the control arms are the same? what all do i need to pull off the 72 to make it work on the 67? I apprieciate it.

67pro-street · 02-14-2004, 04:24 PM

I recently did this exact same thing to my 67. I recommend that you just drop the whole crossmember on both trucks. that way all you have to do is unbolt the old crossmember and then bolt up the new one. When i did it, i didnt get the brake lines off of the donor truck, and the ones on my 67 were different, so i suggest taht you also take off the brake lines. (there is a brass fitting on the left side of the crossmember, so unscrew it from there and you will be fine. And then there should be a butt connector piece for the line going to the back so if you unbolt that one over there also then you should be fine). Lasly, you will need to switch the proportioning valves. I think thats about it. If you dont run into any problems, it should take you about a full day to do. It took me two days because i had to run new brake lines, and i had never done anything like this before. anyways, hope this helps and i hope i didnt leave anything out.

67pro-street

MrGoodpliers · 02-14-2004, 05:06 PM

If you choose not to swap the whole crossmember, be aware that the ball joints are different for these two trucks. Either yank the control arms too, or install new '71-'72 ball joints.

Vince M · 02-14-2004, 08:09 PM

One of the bolt holes on the side of the frame (each side) has to be filed a bit to line up with the later model crossmember. It's not hard. Just take a round hand file and slot the hole to fit. It's not off by much but the bolt wont fit if the hole is not slotted.

Nate003 · 02-14-2004, 09:45 PM

thanks guys, i didn't get any reply's by the time i was leaving to go do it, so i called up WES and he gave me the advice to drop the whole crossmember, and forewarned me about the filing, dropping the whole crossmember is a excellent idea. I also grabbed the brake lines and the power steering and sway bar and power brake booster and master cylinder. thanks tho for all your replies, i apprieciate it.

Blue Beard · 02-14-2004, 09:47 PM

One thing I was told.........

If you're leaving the motor in the frame and changing the front cross member....the engine mounts to this area..........so you'll need to support the motor while its being done....

Nate003 · 02-14-2004, 10:05 PM

yeah it would be a good idea to support the motor, I just took the motors out, was pretty fast because nothing was hooked up and there was no exhaust. just unbolted the motor mounts.

taser · 02-14-2004, 11:49 PM

thought this might help
http://www.jeepgod.net/d44625.html

robby · 02-16-2004, 12:53 AM

maybe I am having a brain fart but I can't visualize "just drop the front crossmember" I took off the upper and lower control arms off of a 72 not long ago with the disc brakes in case I wanted to do that swap and I took off each side two top nuts from the control arm, four nuts off of the "U" bolts for the bottom arm and the tie rod end, and the brake lines. won't that work?

02-14-2004, 03:18 PM	#1
Nate003 Registered User Join Date: Oct 2002 Location: Bremerton Wa Posts: 124	swapping out a 6 lug to a 5 lug, what all do i need to change?please hurry Hi everyone, I am about to go take off the front susp. off of a 72 1/2 ton 5 lug disc and put it on a 67 1/2 ton 6 lug drum front end, I'm curious as to whether the control arms are the same? what all do i need to pull off the 72 to make it work on the 67? I apprieciate it. Last edited by Nate003; 02-14-2004 at 03:29 PM.

02-14-2004, 05:06 PM	#3
MrGoodpliers Registered User Join Date: May 2002 Location: Gainesville, Georgia Posts: 704	If you choose not to swap the whole crossmember, be aware that the ball joints are different for these two trucks. Either yank the control arms too, or install new '71-'72 ball joints. __________________ We made Oklahoma a little after 3, Randy & his brother Bob & my old GMC...

02-14-2004, 08:09 PM	#4
Vince M Senior Member Join Date: Apr 2000 Location: Orlando, FL Posts: 1,076	One of the bolt holes on the side of the frame (each side) has to be filed a bit to line up with the later model crossmember. It's not hard. Just take a round hand file and slot the hole to fit. It's not off by much but the bolt wont fit if the hole is not slotted. __________________ ............................................................ 68 Chevy CST SWB w/LS1, carb & 700r4. Golden Anniversary clone with a few improvements.

02-14-2004, 09:47 PM	#6
Blue Beard Registered User Join Date: Jan 2003 Location: Washington State Posts: 8,831	One thing I was told......... If you're leaving the motor in the frame and changing the front cross member....the engine mounts to this area..........so you'll need to support the motor while its being done.... __________________ 1970 Chev CST 2003 Harley Fatboy 1975 Chevrolet Step Van 1956 Chev Bel Air 1977 Blazer 2WD For Sale $3000.00 1978 Blazer 2WD For Sale $7000.00 1978 Silverado 2005 Monte Carlo

02-14-2004, 11:49 PM	#8
taser Registered User Join Date: Sep 2003 Location: albuqueque Posts: 105	thought this might help http://www.jeepgod.net/d44625.html __________________ 71 blazer 700r4 350 edelbrock cam, 1407 carb, holley intake, hei accel dist

02-14-2004, 04:24 PM	#2
67pro-street Registered User Join Date: Jan 2003 Location: Bellingham, WA Posts: 218	I recently did this exact same thing to my 67. I recommend that you just drop the whole crossmember on both trucks. that way all you have to do is unbolt the old crossmember and then bolt up the new one. When i did it, i didnt get the brake lines off of the donor truck, and the ones on my 67 were different, so i suggest taht you also take off the brake lines. (there is a brass fitting on the left side of the crossmember, so unscrew it from there and you will be fine. And then there should be a butt connector piece for the line going to the back so if you unbolt that one over there also then you should be fine). Lasly, you will need to switch the proportioning valves. I think thats about it. If you dont run into any problems, it should take you about a full day to do. It took me two days because i had to run new brake lines, and i had never done anything like this before. anyways, hope this helps and i hope i didnt leave anything out. 67pro-street

02-14-2004, 09:45 PM	#5
Nate003 Registered User Join Date: Oct 2002 Location: Bremerton Wa Posts: 124	thanks guys, i didn't get any reply's by the time i was leaving to go do it, so i called up WES and he gave me the advice to drop the whole crossmember, and forewarned me about the filing, dropping the whole crossmember is a excellent idea. I also grabbed the brake lines and the power steering and sway bar and power brake booster and master cylinder. thanks tho for all your replies, i apprieciate it.

02-14-2004, 10:05 PM	#7
Nate003 Registered User Join Date: Oct 2002 Location: Bremerton Wa Posts: 124	yeah it would be a good idea to support the motor, I just took the motors out, was pretty fast because nothing was hooked up and there was no exhaust. just unbolted the motor mounts.

02-16-2004, 12:53 AM	#9
robby Semper Fidelis Join Date: Dec 2001 Location: Cedar City, Utah Posts: 654	maybe I am having a brain fart but I can't visualize "just drop the front crossmember" I took off the upper and lower control arms off of a 72 not long ago with the disc brakes in case I wanted to do that swap and I took off each side two top nuts from the control arm, four nuts off of the "U" bolts for the bottom arm and the tie rod end, and the brake lines. won't that work? __________________ 72 Chevy C 20 with 402 For sale 85 GMC K2500 83 Trans Am Cedar City, Utah (Missouri Native)



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