The Stovebolt Site Forums The Parking Lot Big Bolts 72 c50 rear end swap

Ok so I been wanting to put a 2speedrear on my truck for a while and well a month ago I was using truck to haul off some cars with a trailer and got back home and noticed fluid on my rear rims. I assumed it was another of the original brake wheel cylinders going out and I took hub apart to find it was axle lube. And then I find that the previous owner obviously changed wheel bearings on it and when doing so over tightened the inner hub nut that pushes bearing into place and stripped the threads on the inside but the last 5-6 thread on the outter end we're fine making it appear to thread on normal. So it's basically scrap now cuz getting the dye and tap slightly smaller to fix it was gonna cost 400plus.

But lucky for me I just picked up a two speed rear with the Dayton style rims from salvage for 200 bucks so I made out good cuz now I don't need new rims cuz my old axle had the widow makers and the tires were getting bad.

Anyway to the questions.... Wiring the two speed up.... I did notice that the two speed truck had a electrical component mid speed cable between dash and tranny. I snagged that along with axle. My truck doesn't have this and assuming cuz I have a single speed rear. What is this called and what's its duty?

Thanks Mike

That's a small gearbox that changes the speed of the speedometer cable so the instrument panel reflects the actual speed when switching from high to low ratio in the rear end. It should have either a mechanical linkage or maybe a solenoid to make the ratio swap as the selector is moved from high to low and back.
Jerry

Gotchya it all makes sense now. when I started getting all the wiring, I chased that solenoid wire to that gear box and realized it was linked into the speed cable and was very curious to see how this was gonna convert. seems like it will be ok except my gearbox is gonna have to be mounted under truck rather then the firewall cuz my cable coming from dash is long and the two speed trucks dash end was short but I did get the other end of gear box to tranny for my truck but my mounting location will be further under. Does this two speed cable gearbox have to ground to the truck for the solenoid section? The rest is mechanical like a weed eater shaft.

Thanks Mike

Maybe you could go back and get the front axle too, so it matches the rear, have proper wheels? Dayton wheels are made in tubeless sizes also, 22.5 for example.

Ed

Ed if only I found this truck 9 months ago when I needed front tires for my widow makers.... I ended up buying the modern tubeless widow maker replacement rims for 250 a pop then got tires put on them..... Don't worry I'm grinding my teeth as i say it cuz I Waisted some cash there but anyway I'm past that haha.

The rims are 22.5 that I got and they are brand new so they will last me quite some time and I can have new tires put on them anywhere. I'm not really worried about matching rims as long as I can get tires put on at the tire shop is all that matters to me, cuz I'm just using truck to haul gravel for our property and hauling firewood and wood chips as well so safety and maintenance are my concerns.

And to really [censored] in the wheaties! I got a front axle from another c60 a while back cuz it had the dual brake wheel cylinders and wider brakes but had the widow makers. I got that axle mainly just for the extra stopping power. It is a 10 lug rather then the 5 lug front axle I have now. But now thinking about it I wish I didn't get it cuz your right I should just be getting that Dayton front axle.... But we don't have time machines or endless bank accounts so gotta just play the hand that's dealt

So just started measuring u bolts to order some new ones and I ran into a minor hold up.... My truck has 2.5" wide rear leafs and the donor truck had 3" wide leafs and I was wanting to use the overload 3leaf pack in place of my single overload leaf. Reason for this is because my truck has a grain dump bed and they didn't put a full sub frame under the dump bed like most dump body's there is just a piece of thick angle iron to keep dump bed frame from sitting on the actual truck frame. And my 8.25-20tires are close to the bottom of bed when I'm loaded so when I put this new axle in the tires on it are 9-20 so are taller and I'm worried when loaded they might rub. So I was initially thinking if I added the heavier overload leaf pack then when I'm loaded it wouldn't allow me to squat as low and adding an extra inch between axle and frame like a body lift kit would do except this would actuall be leaf springs helping hold the weight instead of the useless lift block. So my question is would it hurt anything if I used this 3" overload leafpack above my 2.5"rear leaf springs? Would I need to put a spacer to fill the 1/2" space between the ubolts and the lower leaf pack section?

And just to assure you I'm not trying to accomplish hauling more weight, just hauling the same 5-6tons max as I have been but without the rear squatin as much for the larger tire clearance....

Thanks Mike

I'm not sure I'd stack 3" springs on top of your 2.5" main springs...it might work, but I wouldn't do it.

Can you just take the spring hangers off the donor truck and move the whole works onto your truck? That might be the easiest way to go...don't forget to get the helper spring frame hardware while you're there. On second thought have the salvage yard cut the donor truck frame and take the entire back half of the truck home. That way you'll have a template for all the needed holes and transfer the axle and springs onto your truck as a unit.

Mike B

Now that can't be the easy way. Haha. I'd rather just put a lift block in to get the clearance I need. Rather then disassembling and reassembling my frame. My truck already has the help spring hardware but my truck only has one helper and the donor truck had 3 helper springs giving more weight holding capacity and more space like a lift block. Therefore holding truck frame higher from ground when loaded. Can't I just put some sleeve washers on the u bolts to fill the space between u bolts and the 2.5" springs? Or maybe fabricate a plate to fill the space and flare the front and back lip so it can't wiggle out over time. All I care about is safe and smooth operation. The riggery won't bother me as long as it's safe and works.

The donor trucks frame works was in pretty roached condition so I wouldn't have felt safe going that route anyway. Cuz my spring blocks are in way better shape structurally. That truck had the reinforced frame and it looked to me the reinforcement part caused the whole frame to rust out from road salt getting up between frame and reinforcment frame crevice. The truck was obviously on the road a lot more then my truck has been.

If I did the fabricated plate option I could use a piece of 1/4" plate on each side filling the space so the axle couldn't shift side to side over time of hitting bumps and stuff. Seems like it would work fine and be way simpler then drilling/cutting the rusted out frame spring hangers and hoping they last the life of my not so rusted truck.

The spring should be retained in position relative to the axle by the center bolt locating tightly in its hole in the spring perch. The U-bolts should not contact the spring leaves as they will wear and weaken the bolts. The spring leaves are restrained from swiveling by clips normally riveted to a leaf and wrapping around others. Some clips are simply bolted around the leaves. If the U-bolts seat correctly around the axle tube and fit the retainer plates, there is no reason to worry about an additional space caused by using 3" retainer plates on 2.5" mains. In my opinion.

I would not put spacers in to fill the gaps and cause more grief. Your mileage may vary.

Ok so yeah I was looking at my current axle I'm gonna remove soon and your right, the only leaf spring the u bolts touch are the top overload leaf spring and the rest of main pack there is a small space so I'm not to worried about it. but glad you mentioned the rubbing issue cuz I'm gonna pass on my spacer plate idea now cuz I didn't think it could hurt but it could rub and over time could cause issues. Thanks I'm gonna continue on with getting 3" wide u bolts to clear the overload leafs and just bolt it down. Gotta clean donor axle up and paint it before reinstalling so she looks good and last me forever....

Well here it is for the people that care.....

Its sits level while loaded now with the 3" overload springs. Second benefit before my rear end swatted causing my front end to lift a bit, making my no power steering, steer way to easy making me unsteady at highway speed.

I have 5 tons of gravel.

Leaf springs seem to have more hold capacity to them then what I got on them. But I'm not planning to haul more weight. But it will give me more suspension action while loaded.

And the drive shaft slip joint space didn't even change when I got the gravel cuz ichecked that right after I paid the quarry before leaving. it was a rough road going to the quarry I went to today. And the bumpy roads didn't even move the zip tie method one of you great peeps told me about. So I feel safe about the swap without changing the driveshaft length.

Also I was able to hit 62 mph in 4th gear high range unloaded and I was going 50 mph 4th gear low range loaded on way home.

I'm still not 100% about what I'm doing when split shifting while driving with a load so im just gonna play it safe till I get the hang of split shifting while driving unloaded first. But I'll get the hang of it soon this is the third drive it's been on since the swap. And the first heavy load test drive and it went great I have to say. This rear end was made for this truck. Idk why they even put that other one on it Haha. It was just such a smooth ride there and back it almost felt like I was driving a different truck cuz the suspension difference and speed and braking lol everything!!!

Thank you for all the helpful info y'all have given me.

Soon to come the power steering gear box swap and power steering assist cylinder install. Along side a front axle swap for wider brakes and 10 lug hub piloted hubs instead of the 5 lug adapter thing that I personally think is unsafe looking. But that's just my opinion/reasoning for the swap. And that front axle is off a different c60 that is probably smashed up and on it's way to China haha.

Why not raise the bed pivot point (body lift)?

Too much extra work Haha. I'm a poor boy who needs to use truck, not fix it all the time. Lol. But there really isn't a reason to body lift it. Everything clears fine now that I cut the wheel wells out of bed sides. Why would you body lift it? Any serious reason for that idea? Or just for looks...