Looks like it's inside the trailing arm, so it's not a shim, more of a washer to spread load. Not certain, but it rings a bell - I think I have them on my 1850. I'll have to check.
Also, didn't the early Sprints have a thicker rear bar? Maybe this was added to stop the extra loaf ripping the bolts out of arms, which is why it's not seen on many cars?
I noticed this too when I fitted the rear ARB to my 1300, as the trailing arms and bushes are flexible, I doubt it's to do with 'shimming up' but not knowing the thickness doesn't help. My only other thought, is that it may prevent fretting on the trailing arm.
I've fitted a couple of rear AR bars to cars that could have done with a bit of spacing. But meh! The bar stretches when bolted up tight!
Like the other sages above, i've never actually SEEN one of these shims in service on a car. I do tend to fit a large penny washer inside the trailing arm rather than the standard small one, but that's just me being me! I've never seen a bolt pull through either!
Steve
'73 2 door Toledo with Vauxhall Carlton 2.0 8v engine (The Carledo)
'78 Sprint Auto with Vauxhall Omega 2.2 16v engine (The Dolomega)
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As Steve says, I fitted as large penny washer in the trailing arm to spread the load one my 1975 1500TC. Also I would have struggled to fit a shim as it was tight, but that could be the many layers of Hammerite!
There were certainly NO shims or spacers on the Triumph Dolomite Sprint from which I salvaged a rear anti-roll bar in mid-1982 for my 1974 Triumph Toledo 1300.
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Nigel A. Skeet
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