Bobbed M35A2 Axle Wrap.

[byrdo]

Recently bobbed my M35A2. I used front springs from a donor truck and installed C&C 2 piece wheels with 46" Michelin XL's. After the truck was finished I took a few test rides everything checked out. My buddy who helped me do the bob noticed significant axle wrap when starting out in 1st gear. Is this a common problem with bobbed deuces on 46's? Has anyone made ladder or track bars from one of these trucks? If so, can you show me some pictures of how it was done. I was thinking of adding a track bar by welding a bracket to the frame just forward of the spring perch then connecting it to the inboard forward axle u bolt with a heim joint and single nut over the existing nut. Do you thing 1/8 inch wall DOM tubing would be strong enough? Should I weld a bracket right to the axle?

 

[wehring]

Check u-bolts...

I get very little wrap using front springs. Check your u-bolt torque values again. May be loose...

Justin
979 997 3112

 

[ivbeenrokd]

If you do end up adding a traction bar here's what we do on most of the Jeeps with full size axles:

Attach the bar at the axle end on the top and bottom so it has good leverage over the axle. Attach the bar at the frame end using a shackle. This allows the axle to move front to back and up and down as it should, but will not allow it to twist so much. Seems to work really well.

 

[rizzo]

If you do end up adding a traction bar here's what we do on most of the Jeeps with full size axles:

Attach the bar at the axle end on the top and bottom so it has good leverage over the axle. Attach the bar at the frame end using a shackle. This allows the axle to move front to back and up and down as it should, but will not allow it to twist so much. Seems to work really well.

I agree

I know several guys using deuce springs and tractor tires and not having problems wit spring wrap. I would investigate it some more

 

[wehring]

another thought...

Another thought... make SURE you have front springs and not trailer springs on front hangers. County the number of leafs and compare to the front springs on your truck. Unlikely but a possibility.

Justin

 

[503m715]

What is your pinion angle? How much tire pressure? Do you have rear shocks? These can contribute to axle wrap.

 

[byrdo]

Thanks for the help.

Thank you all for the input. I did confirm that they are front springs. Pinion angle is not more than a couple of degrees. As of this post the shocks have not been bolted to the frame. They will be by the weekend. Would shocks being disconnected have that much influence on axle wrap? Tire pressure is factory recommend 120psi.

 

[nk14zp]

 

[res0wc18]

is your drive shaft a slip shaft? it needs tp be able to flex and move...

 

[503m715]

Thank you all for the input. I did confirm that they are front springs. Pinion angle is not more than a couple of degrees. As of this post the shocks have not been bolted to the frame. They will be by the weekend. Would shocks being disconnected have that much influence on axle wrap? Tire pressure is factory recommend 120psi.

I do not think the shocks would cause any problems unless something else was wrong. (I still do not have any on the rear and cant tell that I dont) Low tire pressure could contribute, but with the pressure you are running that should not be a problem. A few degrees of pinion angle on my race car made a huge difference in the way torque was transfered to ground. (would cause the car to squat one way and lift the other) You did check the u-bolts as suggested? How did you mount the axle to the spring. (did you use a lifted mount/block) should have ask that first I guess.

 

[byrdo]

Answers

The drive shaft does have the slip yoke in it. It was professionally made by a local shop that specializes in drive shaft and clutch work. Pinion angle is near to original as possible. When I did this I bought my front springs for the bob from eastern surplus. No lift block were required. The axle is mounted to the springs using the factory blocks. Pinion appears to be perfectly parallel to the ground. I will get a video of it this weekend and some pictures of the suspension itself for you to see. The U bolt are torqued as tight as I could get them with a two foot breaker bar. I did not actually torque them to a specific value as the tools were not available to me at the time. I can say that it is the spring that is wrapping from observation. The axle is not moving under the spring. What is the correct torque value for the U-bolts anyway? Maybe, it is just me and not a problem at all. Everything on this truck is so much larger than anything else that I have worked on. Maybe it is a normal amount of flex. I will post the video and get your opinions.

 

[OptimusPrime]

I have the same setup as you byrdo. I am experiencing the same axle wrap. Am contemplating building the track bar as suggested above. Looking forward to seeing that video to compare.

 

[GoHot229]

Can you fabricate stuff? Of course you can, if you did a Bobber, so heres an idea, make some of these 'roughly' , bigger of course but this would cure the wrap alot.

 

[OptimusPrime]

Thanks GoHot229. Forgot about the old hot rod days. I'll give it a try.