T-bar or ARB issue
 

I experienced a strange vibration when driving home last night - approaching 70mph, on a LH corner, accelerating into 5th. Felt a thumping under the driver seat (underbody) for 2-3 seconds, which I never felt again for the remaining 40 mins home.

Viewing side to side, i now notice the OSR arch to tyre gap is bigger than the NSR by 5-7mm - OSF and NSF look as it was previously.

IIRC, if the OSR is high, its means a problem at the NSF, but both front looks ok?

Both rear t-bars were replaced with good used items back in 2011.

Prior to checking RH this morning, i took it for a spin last night up to the local 50mph speed limit - nothing untoward heard or felt when steering in both directions at 50mph

At standstill, could a failed ARB Mount cause ride height issues, or is it more likely to be t-bar? I tried wiggling the rear arb but couldn’t budge it at either end.

Wondering if I can drive it safely 5 miles to the specialist. Would a failed t-bar show up with a more drastic height difference?

Thanks all.

Jack up the car, safely. Climb underneath, with flashlight, inspect the ARB mounts. Failure will be evident. Mine were creaking and groaning on slow off camber inclines, it stopped, did the above and the left side was ripped clean off the car. Buttload of grinding, fitting and welding the "new/old" Wevo RARB consoles.

Thanks - so a failed ARB mount will affect ride height?

I have Wevo mounts fitted.

No. Swaybars only effect the car when the car is leaning.

Not true. Unless you have adjustable drop links, the sway bars will add pre-load. Also, once you add sway bars, the suspension is no longer fully independent. So a bump felt on one side of the car transfer some force to the other side of the car.

No leaning required for either effect.

I have adjustable drop Rennline drop links fitted.

Drove the car back to storage today, approx 10miles of mixed roads. Nothing untoward noise wise, but found the NSR slightly higher than yesterday (just get my finger into the gap, impossible before). NSR still slightly lower than OSR

Perhaps the ride height adjustment on the spring plate got loose?

Are you using high pressure gas shocks? Those raise the ride height when swapped in without making a ride height adjustment, so if one lost pressure you'd expect a sag on that side.

Someone else has suggested the same, although I see no witness marks suggesting things have moved there.

Using standard Boge shocks, with +1mm bigger ARBs, Wevo arb mounts and Rennline droplinks.

Strange how the NSR has suddenly raised itself.