Axle wrap

CasterTroy

CasterTroy

Faster'N You
Joined
Mar 21, 2005
Location
Wallburg
USE to, when I had 3.55 gearing, sometimes with a full tank of gas on inclines, when I eased out the clutch from a stop, my bronco would shake like a crack addict without a fix for 4 days

I THOUGHT that regearing to 4.88 would have made that go away...I was assuming that the low gearing and big tires were just playing havoc on the drivetrain

But it continues to do it when I have more than 1/2 a tank of gas and try to start from a stop on an incline. :mad:


Am I experiencing axle wrap?
 
Sounds like you are experiancing "clutch chatter" . The clutch may have been scorched a bit when wheelin, might have a little oil on it from a leaking intake/ rear main, the pressure plate springs might could be weak or broken, might even have a broken clutch hub spring. coupla things to check.

That it does it more with a full tank, the extra weight would aggrivate it, and spring wrap isn't helping matters.

My '90 runner does this too, and I know it is the POS (AZ) clutch I put in last summer and that my wife slips the shit out of it when she drives it on Saturdays ( you would cringe hearing her back out of the driveway) there is no axle wrap as it is coil and 5 link.

Kevin
 
Yep... sounds like clutch chatter to me, too.

BTDT, thanks to leaking rear main.
 
This happens usually right AFTER I've let the clutch out all the way. Meaning it's OK till the full power of the motor is loaded on the drivetrain.

Would that Still be clutch chatter?

Could it be the fact that the lift utilizes the stock block AND a 2-1/2" block AND a 2" or so spring lift? (Lift was installed prior to my ownership)

Should I pull the 2 blocks and just add a 4" block instead?

Could I have the wrong pinion angle?
 
Have someone do what you're talking about in an empty area, with you either hanging our the passenger's (open) door, or standing to the side...

With that much block going on, it wouldn't surprise me at all if it was wrap.. and what you're feeling is the u-joint hitting its max angle..

Hey, get under yer shit, and have a look at the u-joint area.. any shiny marks on the edges of the yokes? (Look at the picture I attached.. on the very right side, see the clean/shiny spot? Look for that)
 

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Ok, now that you add a little more info, you could possibly be experiancing serious wrap, I wasn't aware you had that much lift block.

Do what Rich said, If you can, you drive and get someone you know that knows what he is looking at, as you'll be more apt to reproduce the condition.

A video of it would be even better, so you could see what was going on, there was a vidcap a few months ago of a guy who did just this, but mounted the camera to the bottom of his Bronco, was pretty interesting to see the suspension movement.

I still wouldn't rule out the clutch.

Kevin
 
I am thinking a little of both.

With that much block - wrap is a very real possibility.

But your clutch may not be the greatest either.
IIRC - When I drove it around, here the clutch seemed a bit touchy.

Also - not meaning to sound too mercenary - but I do have a set of lift springs out of that Green Bronco, that might fit your rear and let you get rid of some of that block.

If you are interested, we can take some measurements.

I think you are eligible for frequent flyer miles - I would cut you a good deal on them.
 
hmm sounds interesting

Hey, what did that guy ever do with the axles from that bronco? he sell em or what?
 
CasterTroy said:
hmm sounds interesting

Hey, what did that guy ever do with the axles from that bronco? he sell em or what?
Click to expand...


I *think* he put the 9" rear in his FS Bronco. (He had me regear the front TTB to 4.56 to match it) I believe he planned on selling the front axle. If you are interested, I can see if I can get hold of him and find out.

BTW - I e-mailed you off-list. Just checking up on things.
 
CT do a shackle flip on the rear. Sky brackets are only $85 or so or you could go the JY route and use the FRONT spring mount to the rear. Net lift depending on shackle is 4-6"
 
Nah... fawk a shackle flip. Everybody likes to do it because it's cheap.... but it's not all it's cracked up to be. He's got to source some F450 shackles or build something beefier so they don't fold, then he'll have to build some new rear packs to counter the additional stress on the springs from the boatloads of wrap he acquired.... and then he's still going to be stuck with lots of AS and a lower roll center.
 
saf-t scissors said:
. He's got to source some F450 shackles or QUOTE]

Got a part # handy? Finally got a chance to work on it yesterday. Got the flip done just need to get a better shackle
Click to expand...
 
Um..... no. In the junkyard, under an F450? Is that good enough? They look just like the 1/8" stamped light-duty ones, but they're out of 1/4" instead.

I think Scott Senko bought his at the dealership..... $25/ea or something.

I noticed them one day at the junkyard and realized I had to have them. ;)
 
Could you not just make them, or do they have some funky bend in them? My shackles are 3/8"...
 
They're not your run-of-the-mill "H" shackle... more of an "A". The frame side captures the bushing inside the shackle, then the other end flares out to match the bushing that's captured in the spring eye.

Bent one:

awww.supermotors.org_getfile_81888_fullsize_Nathan_20059.jpg
 
I saw that picture before I did my shackle flip, and it scared me into bracing mine. I used trailer spring shackles from Northern Tool. I think they were $3 a pair. The holes were even the correct size, so I did not have to drill anything. Just bent them in a vise, and welded them up. Shackles ended up 0.375" thick. I also plated the back side withe some 1/4". They have held up great.

awww.supermotors.org_getfile_131443_fullsize_IMGP0027.JPG


Of course who could deny that this is not the hot setup. :flipoff2:

awww.supermotors.org_getfile_131445_fullsize_right_20side.JPG
 
I'll have part#s on the shackle when I pick them up tomorrow. Ran through the shop was $16 ea.
 
I did these for a friend with a CJ on 44's, they ain't painted or pretty'd up yet but he left black marks in my driveway. The foward shackle mount/crossmember lets the suspension compress and stuff but no wrap. The rear catches the top and bottom of the axle. You could probably get by with just one of these mounted way inboard if you're obessed with flex :) . It would still kill the wrap on the springs I believe.

p369-1112938751.jpg
[/IMG]

Scott
 
maybe furds are different, but GM shackle flips are definantly all they are cracked up to be and then some. as long as you have a trac bar it is the hot setup for cheap lift and good flex
 
one bar is plenty sufficient.. ;)
 
What size tire's do you have? I could have missed alot of info but with a 95 bronco I'm guessing you don't have 44's. I think it's probably the U joints or possibly the clutch. You can find out if it's axle wrap easily get a friend to watch the axle in the same situation. You can also take off hard and will feel vibration in the rearend.
 
Metto said:
maybe furds are different, but GM shackle flips are definantly all they are cracked up to be and then some. as long as you have a trac bar it is the hot setup for cheap lift and good flex
Click to expand...

Metto, don't take this the wrong way, but based on your other posts, I suspect that you're in no position to accurately discuss the pros and cons of a shackle flip. Reading about it on the intarweb is not sufficient experience.

And a TRACK bar goes locates the axle left to right. TRACTION bars prevent axle rotation. :beer:

Edit: What I mean is, if you want to discuss specifics about the change in roll center, antisquat, etc... then discuss specifics. If you have any good ideas about how to use a flipped shackle and a traction bar without generating boatloads of AS, then please share them.
 
meaning what? that i dont wheel? okay i admit it, im a webwheeler and ive never been 4 wheeling. actually i dont even own a truck. even with my shitty mud truck track bars on, my rear flexed much better and had wayyy less axle wrap after i did a shackle flip and ditched the blocks. my gray truck is the same way. sorry if im not captian suspension design oh great moderator
 
Metto said:
even with my shitty mud truck track bars on, my rear flexed much better and had wayyy less axle wrap after i did a shackle flip and ditched the blocks. my gray truck is the same way. sorry if im not captian suspension design oh great moderator
Click to expand...

Case in point.

If you can't discuss a point based on its merits and stick strictly to that topic, stay in chit chat.

Comparing a tension setup with blocks vs. a compression setup with a "shitty mud truck traction bar" isn't comparing apples to apples, and adds little to the discussion.

My thesis is simply that a compression-style shackle setup lowers roll center, slopes the roll axis rearward, and increases anti-squat unnecessarily. These setups require beefier spring packs and traction bars to help offset the wrap and wheel-hop generated by the dropped roll center, and the additional cost of these and other related parts makes the "cost benefit" question a wash. Additionally, even once the suspension is dialed in, a slight change in traction, tire pressure, weight, etc, will make it a hopping bitch again.

Discuss. :flipoff2:
 
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