Differential Nuts are backing off or the Studs are stretching

[Jonathan_Ferguson]

I've always had a bit of Axle Tramp(not Wheel Hop), but these days it's quite gnarly. I replaced the rear Leaf Springs about one and a half years ago and the Axle Tramp did subside, but it's back as gnarly as ever, particularly after I replaced the flogged out Rubber bushes with Polyurethane and all new Pins.
Also, since replacing the Rubber bushes in the front and new Pins and Shackles, I'm getting a huge amount of Dive in the front under heavy braking that wasn't present prior. - The Torque Rod has always been present.

With the Rear third member, when I put the Diff in after the Lock Right install I torqued 'em to the spec of 25Nm, then when I noticed the Diff puking previously(one year afterwards) I torqued it to the specs between an open Diff and an LSD of 26.555 ft/lbs., the next time I whip out the Torque wrench I'll tighten the Nuts to the LSD hausing spec of 47Nm. - Only a quarter of the Nuts need to be increased in Toque, those are on the left side bottom half.
Is this a consequence of Axle Tramp, and is anyone else getting these symptoms?

 

[sandcruiser]

what sort of gasket are you using?

I did mine w/silicone sealant, let it set up for five or ten minutes, then torqued the nuts to whatever the fsm required, more or less. No leaks.

 

[Hilux]

I've always had a bit of Axle Tramp(not Wheel Hop), but these days it's quite gnarly. I replaced the rear Leaf Springs about one and a half years ago and the Axle Tramp did subside, but it's back as gnarly as ever, particularly after I replaced the flogged out Rubber bushes with Polyurethane and all new Pins.
Also, since replacing the Rubber bushes in the front and new Pins and Shackles, I'm getting a huge amount of Dive in the front under heavy braking that wasn't present prior. - The Torque Rod has always been present.

What kind of condition are your shocks in? And what brand are they?

And just how big are the shackles you swapped out?

With the Rear third member, when I put the Diff in after the Lock Right install I torqued 'em to the spec of 25Nm, then when I noticed the Diff puking previously(one year afterwards) I torqued it to the specs between an open Diff and an LSD of 26.555 ft/lbs., the next time I whip out the Torque wrench I'll tighten the Nuts to the LSD hausing spec of 47Nm. - Only a quarter of the Nuts need to be increased in Toque, those are on the left side bottom half.
Is this a consequence of Axle Tramp, and is anyone else getting these symptoms?

1: When you replaced the rubber bushings with poly, you moved up the "weak link".

2: (and I'm sorry) lol, this coming from the guy that wants a his 2L to turn 6,000 rpm to double the power... (I'm laughing WITH you J, not AT you)

3: I'd back off the skinny pedal alittle, see if it subsides. Tell the truth, do you drive it like you stole it? Or drive it like you own it?


And I think the studs are grade 8. Not that they can't stretch, only...highly unlikely. (although they will stretch before they'll break)


Also, I'm gonna assume J, you have a rear locka and small tyres. When you turn, is it power off? (not touching the gas pedal) Or power on? What type of surface are you mainly on?

You know, somethings got to give and I feel that's the cause. IMO the small tryes are gonna move the "weak link" away from the axle shafts. And what comes next? The carrier I believe.

 

[Jonathan_Ferguson]

what sort of gasket are you using?

Paper, I think I may have even greased it aswell.

What kind of condition are your shocks in? And what brand are they?

And just how big are the shackles you swapped out?

New Ranchos done at the same time.
Stock length, but greasable.

3: I'd back off the skinny pedal alittle, see if it subsides. Tell the truth, do you drive it like you stole it? Or drive it like you own it?

Actually I'm quite nice to it, but I will hold wide open throttle whilst waiting for the revs to rise so I can grab the next gear.
Say, on a very slight incline I have to bump the throttle to 1,900 RPM and ease the clutch out very slowly, otherwise if I'm a little too quick on the clutch the revs will bounce back to about idle speed. Even on level ground I have to be very patient and this will still cause the majority of Axle Tramp.

Also, I'm gonna assume J, you have a rear locka and small tyres. When you turn, is it power off? (not touching the gas pedal) Or power on? What type of surface are you mainly on?

I have Interco LTB 31x11.5 and the original 4.56 ratios.
I only get Axle Tramp when easing out the clutch on the street. And, my Lock Right is as smooth as silk, literally.

 

[WristPin]

when was the last time you torqued the u bolts?

 

[Jonathan_Ferguson]

when was the last time you torqued the u bolts?

When I did the Fronts, I did check the U Bolts after a few weeks and I got click click click click, so I didn't bother checking the rears after a period of time. To do list.

 

[Eric_M]

Are your rear tires evenly worn? exactly the same air pressure? did you shear a center pin?

How clean where the mating surfaces before you installed the third? toy gasket or aftermarket?


I would guess your locker is poping lose and thats what may be causing it, but I would check the stuff listed above to make sure everything is as good as you can get it to prolong the locker life and maybe stop your leak.

 

[missouriman]

get rid of the paper gasket it can not take the rock crawling forces.
use gasket former as mentioned above it is more flexable.

as for wheel hope the front end can cause the rear end to hop..

transfer of power thing.
soft springs can make it worse like rears up front. great flex, but when under pressure they can wrap and release sending the released power to the rear wheels.

I can see this at work on my wifes truck with the all pro springs.

my alcans don't seem to do it as bad.

 

[Jonathan_Ferguson]

Well, I found the problem. - The rear Universal Joint is so damn well flogged out.

 

[bkg]

Wheel hop - install a well built traction bar.
gasket - grease is not gasket material and should not have been used.

Install a traction bar, pull the 3rd and fix the gasket with paper and silicone (or other FIPG material) on both sides. If your 3rd member studs are stretching or stripping, install button head bolts from FrontRangeOffroadfab.com.