I picked up a 8.8 xplr axle to swap out in my truck project. The axle under there now is about 2" to wide and I wanted different gearing. The current axle attaches to the bottom of the leaf springs and the xplr is designed to sit on top of the springs. The leaf spring spacing is the same for both axles. If I put it on top of the springs it will sit to low and theres not enough clearance, so I would have to change the shackles or something to raise it back up. Another option is to use a flip kit that is a somewhat U shaped bracket that allows you to mount the axle in the opposite configuration. The last options is to cut the spring brackets off and weld new ones on. I had seen in some other threads people discussing the tubes moving after welding and causing axle alignment problems and also slag or crusty bits on the inside of the tube flaking off and contaminating the internals. At this point I am leaning towards the flip brackets. It looks like the pinion angle is the same and once the u-bolts are tight I cant see how it could twist. Any other ideas?
I’ve never seen an issue relocating the pads, then again I never knew any better. I grind as much of the weld I can without getting into the tube, the hammer and chisel the pad off.
Agree with Tman. I think with stock leafs, a flip of rearend from below to above the springs should be about 6 inch lowering. Which seems just about right for a hot rod truck. But if you are worried about the welding causing some shrinkage distortion, you can just weld on opposite side to offset the new pads welding.
Its when the axle hits the frame and exhaust and theres no more clearance! HaHa The truck has already been lowered and wont go anymore without major work.
If you gotta keep the rear on the bottom of the spring, weld on new pads, you dont even have to take the old ones off if they aren't in the way. Flip kits are rigs created for people that cant weld.
I had a merc that was too low once. But as long as there were no field mice in the road I was OK. Just move the spring pads to the top of the axle tube and run with it. Don't overthink it its just a damned old truck.
I might be off record, but I always pull the axle shafts and center section and degrease the axle housing before welding. I am worry about catching the inside of the housing on fire with the grease and axle oil.
When I did this, I put the springs on top of the housing, then removed the three shortest leaves from the ten leaf spring pack. This brought the truck back down to a more pleasing height. My truck isn't lowered and taking those three leaves out actually made it sit nearly level when done. You can get the spring perches and u-bolts from Currie. They have the right size parts available for the 8.8 housing. I used their perches and u-bolts, but made my own clamp plates. When I welded the perches on, I did three spaced one inch beads, instead of a long continuous weld bead. Being that was all that needed welding, I didn't worry about warpage (Exploder 8.8 housing are thick). If you were to do more than spring pads and a few small tabs, I'd recommend using tools to keep things straight, otherwise don't fret. Before welding them, set them on the housing, under the springs, and adjust the pinion angle at ride height, to get the angle correct. Good luck!
When you are welding on a housing with oil in it you can definitely hear some sizzling inside, but you need a fresh supply of oxygen to keep a fire burning. Even if it starts on fire internally it will burn itself out very quickly. My vote is just weld new pads on your new housing where you want them. Get everything prepped to weld, assemble and put on the vehicle. Set pinion angle and confirm you are centered and then tack in perches. Weld in place after rechecking everything or remove to weld. I really would not worry about rust flaking off or the housing warping enough to matter.
I take an easier route, if no issues with the current rear end, I set the pads level. (On current rear). Then use the angle finder to see how the pinion is setting. Then do the same on the donor rear. Don’t be surprised when you see a 8 or 10 degree difference, where the pads are in location to the springs is why that happens, I/e the springs are not “flat” to reference when the rear is installed.
Even if you could somehow rig up some contraption to mount it under the springs, but use perches that are for above the springs; how would you know the pinion angle would be correct? The only way to do this right is cut all the mounts and perches off that you wont use. Clean up the tubes, and bolt it under your springs with the perches just trapped. Set the pinion angle, and tack weld the perches. Then pull it out and weld it up solid. I've done a bunch of these and never done anything except drain the differential. It should not catch fire, or go up in smoke. I've also been careful welding the mounts or brackets on, and never warped a tube either. It's the only way to do this correctly.
I have done several trucks ..I do no welding at first. Clamp it together with the ubolts and road test to make sue nothing funny is going on and it has the look you want...Then weld it and you can skip weld if you are afraid of distortion. Unless you are building a drag car you dont have to be anal on the welding...Obviously welding installed on the vehicle is more demanding but fuck ups are minimized
The original rear axle looks to be factory welded and eyeballing the new one the angle looks the same. But I think I will go the route of welding on new perches using the methods above. Thanks for the help.
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