maddogwyatt

With the help of a local mechanic, my '93 vert now has a nearly complete set of polybushes. We've done the upper A-arms, and are about to tackle the lower ones.
I want to replace at least the Nyloc nuts on the mounting bolts (maybe the bolts as well) because the nylon inserts in the ones on the upper arms just fell to pieces with age, and it would be sense to buy them before we start.
I've checked that the nuts are 18mm spanner size, and the thread looks to be 10mm, or possibly 11mm. Can anyone confirm the thread size to help me buy the right ones, please? Thanks in anticipation.

WVZR-1

You should be able to reuse the bolts I would think and the nuts will be M12X1.75 and they're prevailing torque and NOT ny-locks but ny-locks could certainly be used.

There should have NOT been ny-locks used anywhere in the original production build. Prevailing torque yes but ny-locks NO.

PLRX

This is the part number for the upper control arm nuts. These nuts are the ones with the nylon locks. They torque to 40 lbs-ft.

11516202
(M20X2.5-6.4)

I dont remember seen any nylon material on the lower control arms hardware.

WVZR-1

That's the first part number that I looked at and I'm pretty confident that's NOT a nut with an insert and just the typical prevailing torque nut that's used by GM. I did though look at an older set of control arms I have and they do appear to have an insert. That older part number was 14060153 but of course isn't available. I mention that only because of the OP's location and it would be quite disappointing to order them from the US and receive them.

Have you had one of the 11516202 nuts in your hand?

PLRX

Yes, at least 4 different times.

The ones on the right

WVZR-1

That's awfully inexpensive for a prevailing torque with an insert but that's good.

cudamax

I want a pair of those trick SPC

PLRX

easy to do alignment changes.

cudamax

u bet and good for 4-6 deg pos caster easily

Hot Rod Roy

Nice, but the question was about the lower control arms.

Volunteer Vette Products ( www.volvette.com ) has these lower control arm nuts listed as p/n 4SU06P @ $5.00 ea. They don't say whether they are Prevailing Torque or Nylocks in their catalog.

WVZR-1

I answered his "lower control arm" question in my first post. The M12X1.75 prevailing torque nut NOT Ny-lock is correct for those. They would likely be "flanged head" also, if the OP needed bolts they would be M12X1.75X85 and would be "flange head" in 10.9 grade. Ny-lock nuts can be purchased in a "flange head" also so if the OP wanted he could of course use them.

I likely created the issue because GM seldom uses ny-lock components in suspension assemblies but rather just prevailing torque. I didn't take into consideration that the control arm shafts aren't steel and the nylon inserted nuts were likely used because of the alloy. The conversation then took a turn.

maddogwyatt

:[I likely created the issue because GM seldom uses ny-lock components in suspension assemblies but rather just prevailing torque. I didn't take into consideration that the control arm shafts aren't steel and the nylon inserted nuts were likely used because of the alloy. The conversation then took a turn.[/QUOTE]

Thanks very much for your help and interest guys. I'll be buying them locally, because we're doing the job in 2 days' time, and I don't want to do it twice! If I can only get NyLocs, I can't see it being a problem. Can you?

maddogwyatt

:[I likely created the issue because GM seldom uses ny-lock components in suspension assemblies but rather just prevailing torque. I didn't take into consideration that the control arm shafts aren't steel and the nylon inserted nuts were likely used because of the alloy. The conversation then took a turn.[/QUOTE]

Thanks very much for your help and interest guys. I'll be buying them locally, because we're doing the job in 2 days' time, and I don't want to do it twice! If I can only get NyLocs, I can't see it being a problem. Can you?

WVZR-1

Thanks very much for your help and interest guys. I'll be buying them locally, because we're doing the job in 2 days' time, and I don't want to do it twice! If I can only get NyLocs, I can't see it being a problem. Can you? [/QUOTE]

If you can only get the nylocks you'll be fine BUT try for the flange head and make sure they're not to tall for the nylock to be effective. I believe you understand and you should have "no problems".

maddogwyatt

The job's now done with no problems. Much easier than the top ones, because we were able to use a press without danger of damaging the alloy. I wasn't expecting to feel any difference, but the steering is definitely sharper around the straight ahead position, and I can place it in the road accurately without trying so hard - useful in the UK where we drive on the left - you need to know you're inside the white line!! Thanks again for your help.
p.s. Going on a Corvette run across Dartmoor soon with the South-West branch of the Corvette Club UK. Can't wait!