Thread: rear link arm bolt snapped

Hi Steve - how many km do you have on "scratchy"?

120,000 k just got two new super seeded bolts fitted and they have a shank at the top and are not fully threaded. Apparently the full thread prevented the bushes from moving and placed a lot of pressure on the bolt where it exits the threat in the hub. the new design allows the link am to move in the bushes and eliminates the pressure.

I am surprised that Land Rover hasn't made a recall for this there is clearly something wrong with the original design and this could prove disastrous if it happens on the highway

Thanks Steve,
I read the trip report yesterday, not a pleasant thing to happen where it did. You all did well to get a fix in place.
THere has been a lot of discussion in the States on this as well. This link is from the D3 forum:
NW Challenge Trip Report!!! - Land Rover and Range Rover Forums
There are some pictures on page 6 of the original fitting fully threaded bolt compared with the new one.

Steve, do you know if the bolt had been removed at any stage, there is a lot of discussion on the thread above regarding removal of the bolt for 4 wheel alignment and some suggestion that the service manual states that if the bolt is removed it should be disposed of and a new one fitted.

In the mean time, I will have to find a couple of spares.

Cheers
Mike

So how many aulro'ers have had this failure?

Originally Posted by Steve223

120,000 k just got two new super seeded bolts fitted and they have a shank at the top and are not fully threaded. Apparently the full thread prevented the bushes from moving and placed a lot of pressure on the bolt where it exits the threat in the hub. the new design allows the link am to move in the bushes and eliminates the pressure.

This doesn't sound right as the bush's steel insert in the bush cannot be allowed to move otherwise the insert, the washer and the bolt will wear. I suspect the bolts are undersized for the job so perhaps the bolts need to be replaced on a regular basis to prevent failures from fatigue for vehicles used off the tarmac that are therefore subjected to rougher treatment of the rear wheels.

I'll remove one from my D4 to see if LR has increased the bolt size.

Originally Posted by Graeme

This doesn't sound right as the bush's steel insert in the bush cannot be allowed to move otherwise the insert, the washer and the bolt will wear. I suspect the bolts are undersized for the job so perhaps the bolts need to be replaced on a regular basis to prevent failures from fatigue for vehicles used off the tarmac that are therefore subjected to rougher treatment of the rear wheels.

I'll remove one from my D4 to see if LR has increased the bolt size.

I suspect you are right. The bolt with an unthreaded section is simply how it should have been designed/manufactured in the first place.

LR would have done better to not have the captive washer because it requires the thread to be formed by partially raising it on a smaller diameter bolt. A normal bolt with the thread totally cut into the metal would be a stronger bolt and have the advantage of properly fitting the bush centre spacer. As it is now the bolt is smaller diameter than the bush hole except for the section where the thread has been raised. I've not previously seen bolts in such important roles with captive washers.

Its also possible that there isn't enough clearance between the washer and the link rod causing the link rod to apply force directly to the top of the bolt when at extreme angles. If this is the cause then a smaller spacer washer that fits inside the link's hole should be fitted against the bush then the original larger washer to prevent a flogged-out bush from allowing the link to simply pull off the bolt. Its hard to imagine that a bolt that size just shears when its surrounded by a rubber bush so the jamming possibility is worth investigating.