Traction bar fab and cost

[seschev3]

Traction bar fab and cost (pics)

Finally finished the fab of my traction bar and crossmember. Thought I would share some pics and cost for us that do not have the money, but have the tools.

8' of 1.5" x 120 $25
3' of 1.75" x 120 $10
1' of 3" x 3/16 flat $5
1 2.5" johnny joint $40
3 1.75" greasable HD bushings ORD $54
1 set of traction bar mount plates ORD $25
1 pair HD shackle plates ORD $14
Rattle can $5

Total $178 Half the cost and it is custom fit to your rig.

 

[Blazr77400]

Why not hook the traction bar shackle right to the crossmember instead of that short section of tube?
The way you have it now it seems that it would try and twist the tube when the axle tries to wrap.

 

[seschev3]

The bushing would have to be larger than the shackle and the poly inserts so the shackle would not contact the crossmember. I could have shortened the stub out a bit, but I was using a notcher and that was as short as I was able to get it. I have 350 hp and around 400 ft lbs of torque and have been romping on it pretty good. It seems to be holding up good, but a good run in the trails may prove different. I am going to take it to Hollister for the Blazerfest and see how she does. And I am going camping in a couple weeks pulling my 27' travel trailer, so that might be a good test. It has stopped my axle wrap and improved my acceleration. My tranny has a firm shift and use to wrap the axle on every shift killing my momentum. It is my first traction bar that I made so any critics or ideas are welcome. Thanks for the input.

 

[rdn2blazer]

nice job, welds look good. yes you will know after some hard wheelin if it will hold up or not. thats the great thing about knowing how to fab, and alittle trial and error. if it dont work, build another one.

 

[ntsqd]

Eventually it'll break, too much leverage on the weld btwn the x-member tube and the stand-off tube w/o some sort of gusset headed up high somewhere. Nice job though.

A suggestion, the way you made the tabs that bolt to the frame? Make two of those with holes in both ends. Then slide the x-member thru one pair of holes and the bushing tube thru the other. Could then plate it top and bottom if you want. Might want to round those tab corners. I can garuntee you that I'd smack my head on them.

 

[tRustyK5]

I'm wondering why you used greasable bolts at the diff end. ntsqd makes a good point at the shackle end. A hard launch will pull upwards on the stub and I'd predict you'll have eventual problems there.

Wheeling it will find the weak links, but overall i think the design should work fine once the bugs get worked out.
Rene

 

[seschev3]

Thanks for the input. I will definitely strengthen the crossmember design. I appreciate the knowledge and ideas. Thanks

 

[jekbrown]

cool beans. 1 Question, you have 4 bushing'd (not a word, I know) connections there... how did you determine which was best for the johnny joint? would another JJ at the other end of the shackle be beneficial?

j

 

[seschev3]

I researched different designs. The one current location of the jj is a definite pivot point when one tire is up or down and the other side of the axle moves forward or back. And yes you can add additional jj at the axle or shackle, but for my intesions this works and is less expensive. jj's are $40 a pop. If you do mostly rock crawlin', additional jj's would be more practical.

 

[jekbrown]

yeah, thats what I was wondering... cause I have two RE-joints that I won for free in a raffle... might be able to use them for this. I probably have some spare bushings laying around too. All I'd need is some tube and I could set something similar up. Cool. Thanks much for posting this stuff. You should try ramping the rig both with and without the bar attached to see the difference in flex... that'd be cool.

j

 

[jekbrown]

I'm wondering why you used greasable bolts at the diff end.

now that I look at it, I'm wondering about this too... I don't know crap about designing traction bars, but it doesn't seem like the diff end can really move very much at all just lookin at the two mounting points and where they are.

interesting to compare the one from MOO and you'res...

I know the MOO one is designed to mount directly over the center of the axle, so that changes things... but the diff-connection doesn't use bushings and the x-member end doesnt use a shackle or orbital bushings or anything either. I see it is threaded near the x-member... is that just to adjust for length or does the bar actually rotate about that axis? (wristing, i think its called?)

I have these two RE joints... and I wanted to get a BTF 14b truss anyway. Hmmm.. maybe I should draw something on CAD and see what you guys think...

j

 

[az-k5]

Does having it so far off to one side make a difference?

 

[jekbrown]

yeah, thats where Im thinking the difference in design comes from. The MOO one doesnt even have a shackle or anything... I guess being right above the diffs centerline eliminates the need for it?

I have seen ones similar to MOOs... think Tim posted pics before he got banned. In his, the attachment points on the diff end were bushing'd and ran perpendicular to the axle... which I assumed allowed for more one-tire stuffed-other-tire-drooped suspension action. MOOs doesn't pivot in that axis at all on the diff end and depending on whether or not the other end can "wrist" it may/may not allow much pivoting action at the other end either. hmmm... this thread may need to get moved to center of gravity the way its going. I wanna learn what I can about these types of trac bars so I can make my own.

j

 

[Fubeca]

MOO's looks like it has a slip joint towards the top. That would allow it to twist and to move in and out.

 

[R72K5]

i had a 72 k5 i once that someone had made a setup with soem 1x2" solid steel bar, real simple,.. from axle housing to frame rails, just big bolt for pivot, no bushings or anything,

i dunno if it worked cuz was no engine in the k5

but i have the bars still, up in attic,

 

[jekbrown]

MOO's looks like it has a slip joint towards the top. That would allow it to twist and to move in and out.

yeah, i couldnt really tell from that pic... it looks like it might be threaded...like a suspension link or something... to adjust for length. Not sure if it is free to rotate on said threads... or of your eyes are better than mine and its sold sort of slip joint. hmmm...

j

 

[big pappa b]

The slip shaft rides in a 4 inch long bronze oil impregnated bushing and does not require lubrication. The shaft has 6 inches of slip which is way more than most suspensions require.

[/QUOTE]

 

[jekbrown]

ooooo, OK. cool, thanks for the info!

j

 

[85m1009]

The shaft will rotate 360 degrees and has at least 6 inches of slip. If you have an extremely flexy suspension we can substitute the poly bushing with an orbit eye to allow for what I term "rear axle steer". The tubing we use is a high strength tubing that can actually flex and return to normal which allows for a lot of "rear axle steer" and the poly bushing has a lower durometer rating which means it is more flexible than standard spring eye bushings. Running in the center eliminates the bind encountered with off centered traction bars. It has the added benifit of being out of harms way. We have been working on the design for over two years and have applied for a patent on the design.