Kevbo
02-06-2002, 03:40 PM
Recent power improvements have created a fairly serious wheel-hop, spring wrap situation....I now have enough torque and power to break something. I'm looking for a good solution that will not reduce already poor articulation (improvement would be nice, but not the main goal). I'd prefer NOT to reduce ground clearance either.
Let me say this truck is primarly street driven, but it also gets used to carry a pop-up, slide-in camper places it really shouldn't. It's a F-250, Powerstroke Diesel, extended cab, and it ain't never going to be a serious trail rig. Serious trail rig may eventually get towed behind it, but I have no illusions of being anywhere "serious" with this truck. It does sport a winch and and airlocker rear....Something this big is a real PITA when it is stuck, and I don't like being totally helpless.
Anyway, I figure my problem shares a lot in common with "real" rigs. You guys are the best place to ask, and thinking about it could result in ideas applicable to the trail. Also, I have been using this truck to get my feet wet with modification and fabrication...skills I hope to use on a "real" trail rig sometime.
I know this problem is typically seen with tall lift blocks, big tires, and soft springs, but in my case its all about the engine.
Hop/wrap problem exists with stock rear springs, blocks, and stock tire size. Slightly larger tires are planned, but stock rims will be kept...yeah, I AM probably asking the wrong bunch of guys!
I've looked at all the standard solutions. Everything I've seen off the shelf seems to have binding issues, ground clearance issues, or both. Fabrication is not a problem, but I'd like to hit the target with one shot, and of course simpler is always better, provided it always works, and never breaks.
If it wern't for ground clearance, I'd consider single traction bars connected below the axle.
My current best idea is a single, central ladder bar, attached to pumpkin (with bushings), and a heim jointed shackle mounted in the front. This will keep pinion shaft pointed at the carrier bearing. It will control only the pinion angle...the springs would locate axle as normal.
To avoid binding the springs, I'm thinking of making some two-piece, hinged blocks that will replace. the stock lift blocks. Lower piece would be wider, with U-bolts well outboard of current location. Upper piece would connect to upper spring plate with straight bolts, possibly tapped into upper part of hinge. (Welding, and/or mill work are not a problem)
I know if I put the shackle in the right place, and made the ladder bar just the right length, I could leave spring mounts alone, but
I think this might increase articulation a little, much like wristed-arm does for front axles. "Wristing" would be on both sides, with the central ladder bar controlling pinion angle. This way, ladder bar can attach to existing cross-member above carrier bearing, as length is non-critical.
As for the actual "hinge", I'm not sure if polly bushings or bronze would best. Poly might allow more articulation, as springs wouldn't have to twist as much. There will still be some binding, as the springs will be pulled togethor when axle articulates.
I worry that poly bushings would collapse from taking twice weight that sping bushings normally get. I do carry like 1500# in the bed, when the camper is on.
I realize this setup will still allow alternating right-left wheel-hop, but ladder-bar should prevent any dirveline problems.
I'm looking for input, and trying to simplfy where possible. If anyone has made something like the hinged lift blocks I discribed, I'd sure like to see a picture.
ciao, Kevin
Let me say this truck is primarly street driven, but it also gets used to carry a pop-up, slide-in camper places it really shouldn't. It's a F-250, Powerstroke Diesel, extended cab, and it ain't never going to be a serious trail rig. Serious trail rig may eventually get towed behind it, but I have no illusions of being anywhere "serious" with this truck. It does sport a winch and and airlocker rear....Something this big is a real PITA when it is stuck, and I don't like being totally helpless.
Anyway, I figure my problem shares a lot in common with "real" rigs. You guys are the best place to ask, and thinking about it could result in ideas applicable to the trail. Also, I have been using this truck to get my feet wet with modification and fabrication...skills I hope to use on a "real" trail rig sometime.
I know this problem is typically seen with tall lift blocks, big tires, and soft springs, but in my case its all about the engine.
Hop/wrap problem exists with stock rear springs, blocks, and stock tire size. Slightly larger tires are planned, but stock rims will be kept...yeah, I AM probably asking the wrong bunch of guys!
I've looked at all the standard solutions. Everything I've seen off the shelf seems to have binding issues, ground clearance issues, or both. Fabrication is not a problem, but I'd like to hit the target with one shot, and of course simpler is always better, provided it always works, and never breaks.
If it wern't for ground clearance, I'd consider single traction bars connected below the axle.
My current best idea is a single, central ladder bar, attached to pumpkin (with bushings), and a heim jointed shackle mounted in the front. This will keep pinion shaft pointed at the carrier bearing. It will control only the pinion angle...the springs would locate axle as normal.
To avoid binding the springs, I'm thinking of making some two-piece, hinged blocks that will replace. the stock lift blocks. Lower piece would be wider, with U-bolts well outboard of current location. Upper piece would connect to upper spring plate with straight bolts, possibly tapped into upper part of hinge. (Welding, and/or mill work are not a problem)
I know if I put the shackle in the right place, and made the ladder bar just the right length, I could leave spring mounts alone, but
I think this might increase articulation a little, much like wristed-arm does for front axles. "Wristing" would be on both sides, with the central ladder bar controlling pinion angle. This way, ladder bar can attach to existing cross-member above carrier bearing, as length is non-critical.
As for the actual "hinge", I'm not sure if polly bushings or bronze would best. Poly might allow more articulation, as springs wouldn't have to twist as much. There will still be some binding, as the springs will be pulled togethor when axle articulates.
I worry that poly bushings would collapse from taking twice weight that sping bushings normally get. I do carry like 1500# in the bed, when the camper is on.
I realize this setup will still allow alternating right-left wheel-hop, but ladder-bar should prevent any dirveline problems.
I'm looking for input, and trying to simplfy where possible. If anyone has made something like the hinged lift blocks I discribed, I'd sure like to see a picture.
ciao, Kevin