'84 318i.. 51mm or 47mm?

[jRonin]

So, I'm looking to replace my suspension on my e30, but I've been told by a few people now that apparently the early 318's had two different diameter front housings, but no one could tell me how to figure out which I had short of try to put a shock in it. So my question is..


1) Is there a way to tell what diameter I have without tearing down the suspension?


2) If I have the 47mm housings, will they swap with the 51mm from a later model e30?


Thanks in advance for any support

[Blackout]

Yes and Yes.

[reelizmpro]

84-85 318i's were 45mm with rear drums as standard unless they've been changed at some point. Definitely verify you have 45mm struts with the dollar test before buying shocks.

[jRonin]

Yes and Yes.

Awesome! Thank you! Probably could've measured a string, but the $$ looks a lot simpler.. lol.. I'll be checking that immediately after work.

[prisonerofdoom83]

That picture on the dollar is of the strut insert or the strut housing? So kinda just take the tire off and roll the dollar around . I have a 91 318i

[jeffnhiscars]

Just look at the lock nut. The 45mm has the threads on the outside of the housing whereas the 51 is threaded internally.

Yes you can swap in a 51 but keep in mind that the 84 318 weighs 23xx lbs soaking wet and the replacement dampers are valved to that weight. If you go to 51s your shock options will be designed for a car that weighs 3-400lbs more.