mx5cartalk.com

Over time I have had some temperamental shuddering coming from my rear passenger wheel. It seems to only occur in reverse and sometimes in first gear. After doing some research, I have reason to believe it is a bad U-Joint. My car is a 1990 NA6.

How would I go about making sure that it is in fact the U-Joint and what would be the best way to replace it? I read that the driveshaft and U-Joint are one unit? I think that's only for the NA8+ but someone said it was the case for the NA6 as well.

MX5 drive shaft rarely give trouble.

The rear brake calipers are known to seize, specially on the NA's
A sticking caliper could produce the shudder.

Have you checked they are releasing and moving correctly!

I had a rear caliper seizing on my NA - a real basic quick way to check is put your hand on the rim and check the temperature - my rim got rather warm compared to the others.. (and a bit stinky..)

Another consideration given it occurs in reverse, & occasionally first gear, is a loose PPF bolt or a crack in the PPF:
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