The GMC CCKW

Has anyone ever replaced the rear springs on the truck, one side at a time replacing the whole unit at the trunion bearing?

Mine are starting to curve backwards and the U-bolts are rotting. The USMC truck has a beautiful set, soooo.

What I was thinking of was:

*** Jack up the truck and put it on stands

*** removing the driveshafts (3)

*** removing the brake lines one one side (maybe if they were not long enough)

*** Popping the upper torque rod

*** Popping the lower torque rods on one side

*** moving the axles apart on that side till they fell off of the spring
on that side

*** remove the spring assy by removing the trunion bearing assy.

*** replace the spring with the new(er) spring assy

*** reverse procedure except for drive shafts

*** do other side

*** replace upper torque rods

*** reinstall driveshafts

The idea is to keep the axle from flopping over from the weight of the carrier (banjo) and pointing down. The spring on the opposite side will do that being captivated by the loop over the spring if this procedure works.

Comments?

Hi Doc

Sounds like you've got the plan all worked out
I'm just not sure about the "moving axles apart" part I think the opposite side may offer to much resistance ???? hope not

Good luck!
John

Alas, it won't work

There is not enough room to slide the spring assy sideways w/o hitting the backing plate on the axle housing. Grrrrr

I will have to do it the old fashion way which will be a lot harder and take much longer

Take is slow and be careful I m sure there are a few very Heavy bits and pieces any of which could ruin your day if they move in a unexpected way .

Good Luck Doc. Thaqt is a lot more ambitious than I want to be.

Good Luck Doc. Thaqt is a lot more ambitious than I want to be.

Actually, I woke up last night and have a brainstorm (or nightmare)

Suppose I have the truck raised up a bit and after I separate the axles so that the spring is free, I rotate the spring assy so that it points up. That way, if it clears the side of the frame (which I think it should), it does not matter where the axle backing plates are, just the floor/ground would interfere with it!

I did not get a chance to look at it tonight but it might just work! I will be VERY happy if it does!

Steve

I replaced the springs on my own truck a couple of years ago. If you are cutting the u-bolts off (you mention bad rusting), the springs can be removed by jacking the chassis up to remove all weight from them, then unbolting just one end of one upper torque-rod to allow that axle to tilt away from the other.

This gives enough room to allow the spring to slide back (or forward) out of one axle keeper, then up & out of the other when the spring seat bolts are loosened & the u-bolts are cut off. It's not that hard to remove & refit the torque-rods if you are working on a bare chassis; but with a body still on, it would be much more difficult.

I took the trunnion shaft off at the same time because I had to make a new chassis cross member due to rust.I machined seal diameters into the spring seats & onto the trunnion shaft to allow me to use neoprene seals & get away from the original felt ones. It was a few hours work but I was half-way there anyhow so.....

I hope this all helps. My truck has Banjo axles etc. but I don't think there would be any difference in the case of Timken. Regarding the top torque-rod removal, it may be easiest to leave the tapered pin undisturbed & just unbolt the mounting bracket from the chassis cross member.

Good luck!

Ken B.

Hows the progress on your Spring replacement going ? I guess you going to get them rebuilt and re-arched or will you need to replace them completely ?

I won't do the spring replacement till next year.

Regarding the torque rods: I have the seperator tool and it works quite well if you can get a good wind up on it with a big heavy hammer....

What does this tool look like? I have always had good success with a crowbar and a heavy hammer.

-Lars Svaasand, Norway

It looks like a balljoint seperator. Works quite well if you can get a good swing on the sledge hammer on it. One or two hits and it is off. Leave the nut on the torque rod, but loose so the rod doesn't fly off. I had the tool fly off and hit me in the stomach....

It also helps to be rugged. Torque Rods are one of the more difficult tasks on the CCKW. Am sure many have Torque Rods that need changing.
Banjo Rods are in short supply due to DUKW owners buying them all up over the years. Banjo and Split are different length.