Rear end conversion

[profe56]

Someone in the forum has installed or swap a rear end from 73 and up in a C10 67-72 1/2 ton can I see pictures if you have made this conversion.

[BCOWANWHEELS]

73+up is leaf springs

[57larry]

73 & up have leaf springs. I'd be interested if you can use the 73 with some sort of coil spring conversion

[highperf4x4]

Why convert the springs? The 67-72 GMC's had leaf springs too. Get your spring mounts from one of them.

[90\87Formula]

Originally Posted by 57larry

73 & up have leaf springs. I'd be interested if you can use the 73 with some sort of coil spring conversion

Check this link for a conversion kit. http://www.classicperform.com/Store/...ck/6072RCK.htm

[Tx Firefighter]

I've done it a few times. Here is an 80 model rear I converted a few months ago.

Remove shock mounts and spring pads.



Weld on new coil spring saddles (ECE parts)


Powdercoat:



Use ECE Super Track bar to locate the new rearend side to side.

[Pont406]

Did you use a mig welder? I might try this.

[Tx Firefighter]

I don't remember which I used. I use stick welder or MIG depending on which stage of the moon we're in that day. Any kind of welder that has proper power will do the job. It looks like I used MIG though.

[90\87Formula]

Originally Posted by Tx Firefighter

I've done it a few times. Use ECE Super Track bar to locate the new rearend side to side.

What about the shock mounts?

[Tx Firefighter]

They don't have anything to do with the rearend on a coil spring truck.

[90\87Formula]

Originally Posted by Tx Firefighter

They don't have anything to do with the rearend on a coil spring truck.

I understand that, as far as installing the rearend; but we don't want the truck continually bouncing.

[Tx Firefighter]

I guess I am still confused. The shocks mount to the trailing arms. To do this swap, you don't have to fool with the shock mounts at all.

[90\87Formula]

Originally Posted by Tx Firefighter

I guess I am still confused. The shocks mount to the trailing arms. To do this swap, you don't have to fool with the shock mounts at all.

My bad. It's been a really long time since I actually looked/noticed where they were mounted. Never did any work on a rearend, except change the brake shoes; many years ago. AND my truck hasn't been street driven in at least 9 years.

Sorry for hijacking your thread profe56

[Longhorn Man]

Out of morbid curiosity, why go from a 12 bolt to a 10 bolt rear?

[57larry]

my 73 has a stock 12 bolt

[haysonj]

Here's a 73 14 bolt in a 69 4x4 I had to move the spring perches out as I widened the springs out 2 inches to get more stability for towing.

[Tx Firefighter]

Originally Posted by Longhorn Man

Out of morbid curiosity, why go from a 12 bolt to a 10 bolt rear?

Who me ? That is a 12 bolt out of the 80. I did it for 5 lug and highway gears.

[profe56]

Thanks TX FIREFIGTHER for the pictures and everyone taking part in the topic for all the information, the project to use a newest rear end is because I upgrade front disc brakes in my 69 C10 and firstable I need 5 lugs in rear, second I would probably find out a pos rear end, there is in Otay Mesa junk yards where you pic your parts and pay not much. is there any way to see if a rear end is pos without open the cover?
the rearend must be same wide, is there any problem alignament if is more or less wide
thnk you

[Longhorn Man]

i thought they went to a 10 bolt in 73.
Thanks.

[dragitvinn]

Can anyone help
I have a 69 Chevy c20 with a 8 lug rear end. I bought the truck used and don't know where the rear came from.. when i drive the truck i get shaking from the back of the truck at about 55-65mph.. I looked under the truck and it looks like the rear diff tilted down where it meets the drive shaft... It also is not centered to the truck its over towards the pass side 1 inch.. Can the rear being off centered be adjusted with an adjustable pan-hard bar? Should it be tilted downward toward the front of the rear end?

[Already Gone]

[QUOTE=Tx Firefighter;3516478]I've done it a few times. Here is an 80 model rear I converted a few months ago.



Weld on new coil spring saddles (ECE parts)



How did you figure out where to weld the saddles?

[dragitvinn]

Is it suppose to be on a downward tilt?

[profe56]

I still looking on the rearend I could buy, but CHEVY or GMC Vans could be an opption too?
because I saw a lot specially vanduras, 10s,20s and 30s.
How do you think are the ratios in vans?

[joe b]

A van rear will be too wide

[chevy_mike]

[quote=Already Gone;3563196]

Originally Posted by Tx Firefighter

I've done it a few times. Here is an 80 model rear I converted a few months ago.



Weld on new coil spring saddles (ECE parts)



How did you figure out where to weld the saddles?

I did this same swap, '73 C10, which gave me 5 on 5 lug pattern and 3.42 gear (stock is 4.11 in my '68 rear end).

Using an angle finder to setup the saddle angles. I checked what stock was and just set everything on the '73 rear end to match. As for side to side, lots of measuring, to make sure they were equal distances from the brake flange. Tack welded the saddles then took the rear end back out and did the full welding on jack stands, where it was easier to get to.

Angle finder


Welded up