Thread: 98 110 violent front end shake - harmonic

I have had the death wobbles twice in RRCs.
The first time was in Riyadh in an 81 where the mechanic at the dealer had done the LH swivel plate up finger tight and then fitted the lock plates.
The entire swivel plate was moving. It was so violent it blew the top shaft seal out of the steering box.

The second time took me years to find in my 92. It always had a "kick' when I hit a bump. I did all those things you list. Finally I rebuilt the RH swivel as it was the only thing not replaced, even though it didn't leak and had good preload.

The problem was that the assembler in the factory had "jacked" the swivel bearing cup when installing and it was not sitting square on its seat.

So in both my cases it was top swivel bearing related. Did you check that the cup "rang true" when you replaced them? The sound is distinctly different when they are fully seated. Have you rechecked that the bolts holding the swivel plates are tight , as they may have loosened if a cup was not fully home.

Regards Philip A

notch the bracket out so you don't have to disconnect the brake line.

Originally Posted by PhilipA

I have had the death wobbles twice in RRCs.
The first time was in Riyadh in an 81 where the mechanic at the dealer had done the LH swivel plate up finger tight and then fitted the lock plates.
The entire swivel plate was moving. It was so violent it blew the top shaft seal out of the steering box.

The second time took me years to find in my 92. It always had a "kick' when I hit a bump. I did all those things you list. Finally I rebuilt the RH swivel as it was the only thing not replaced, even though it didn't leak and had good preload.

The problem was that the assembler in the factory had "jacked" the swivel bearing cup when installing and it was not sitting square on its seat.

So in both my cases it was top swivel bearing related. Did you check that the cup "rang true" when you replaced them? The sound is distinctly different when they are fully seated. Have you rechecked that the bolts holding the swivel plates are tight , as they may have loosened if a cup was not fully home.

Regards Philip A

Thanks Philip A,

I did not "ring" them, I have not heard of that before (and it wasnt in the WSM )

I did how ever visually check from inside the swivel ball when I was seating the cups, that they look flat all round and even. Having read here that when seating any cup with hammer rather than a press, it is easy for the cup to "bounce" on that last blow. Better to use light taps at the end, which I did.

I will not rule it out though.

I just removed the right wheel/tyre and track rod. Without removing the caliper and hub (due to LRs brilliant bracket design) I did check the whole assembly for feel. It felt good, not too loose. I also checked top swivel pin bolts, they are as tight as the day I torqued them up.

Earlier today I also removed the drag link and re centralised the steering box. Full lock to LH and then 2 full revolutions back to centre. The steering wheel was 1 spline out. I re fitted it in the new centre location. Took it for a drive and now it felt worse (of coarse) still pulling to the right and now steering wheel and road wheels out of alignment with each other. I then adjusted the drag link to bring the road wheels back in line with the steering wheel. Now back in alignment, but still wants to drift right if I let the steering wheel go. Maybe not quite as much as before, but certainly not more than 10-20% improvement...

Originally Posted by jboot51

notch the bracket out so you don't have to disconnect the brake line.

shame LR did not think of that....seriously, who comes up with the idea of having to disconect brake lines (which means bleeding the brake system) to work on the whole swivel assembly, on top of which the rebuild procedure has you do up, then undo the swivel bolts to fit that stupid bracket..

I have drawn up new brackets in slightly thicker material witha little change so it wont be so weak as if I just slotted the LR one.

When I get these from the laser cutter, I will check the pre load on the right hand swivel...

Originally Posted by uninformed

shame LR did not think of that....seriously, who comes up with the idea of having to disconect brake lines (which means bleeding the brake system) to work on the whole swivel assembly, on top of which the rebuild procedure has you do up, then undo the swivel bolts to fit that stupid bracket..

I have drawn up new brackets in slightly thicker material witha little change so it wont be so weak as if I just slotted the LR one.

When I get these from the laser cutter, I will check the pre load on the right hand swivel...

Maybe I"m confused, but you realise the brake line comes off the bracket via a push on clip. You can then push the line out of the way to access the bolts on top. I've removed shims on top of my swivels, but never had to open up any break lines or bleed the breaks...

Originally Posted by Judo

Maybe I"m confused, but you realise the brake line comes off the bracket via a push on clip. You can then push the line out of the way to access the bolts on top. I've removed shims on top of my swivels, but never had to open up any break lines or bleed the breaks...

what vehicle are you talking about?

Well, Disco, but I thought everything on the TDI Defender hubs were the same as a TDI Disco? Maybe that's my confusion....

Originally Posted by Judo

I thought everything on the TDI Defender hubs were the same as a TDI Disco?

FYI - TDI Defender hubs do not have a slotted bracket/plate for the brake hose. It's a common mod that when we do this job, many owners slot the plate to make the job easier next time so we don't need to re-bleed the brakes.