Rusty front strut housings

[D.Martijn]

Hey guys,


I'm currently getting started with replacing the front shock absorbers on my uncle's iX Touring.
I'm wondering what I should do, replace the housings with better used ones? I was thinking about cutting 2-3cm off and welding a new sleeve on them with the same thread like the new nut. What are your suggestions?

This is what I discovered when removing them from the car
Well, that doesn't look good..


Underside of the strut bearings, on the top side there are very big flakes.
The side of the car itself looks good, just surface rust.


Upper spring perch is also quite rusty, should I replace it?
It's fairly thick metal though


Some hammer and chisel work and a final twist with the pipe wrench and they came right out! What..

[e30davie]

Have these struts been on the Titanic?

Give them a go with a wire wheel and paint. But if the steel is thin in sections from rust I'd personally be looking for new ones.

[Kershaw]

That's honestly going to be OK. The metal still looks like it extends to the original point and it's not eaten completely through. Clean them up and paint them. Make sure you clean into the area where the spring perch mounts. The spring hats don't look like there is any rubbing from the mount onto them, so they're probably ok. I've had 2 rusty sets deform on me during rallycross so I would never run an old set again. YMMV, but cleaning them up and painting them is probably the simplest solution.

I'm posting links so you can zoom in. You can see how bad this strut was, the top 2-3 threads were completely gone it was so rusted. The only safe fix here is to section the struts and weld new threads. The good news is rear wheel drive e30 struts are cheap and plentiful (i found a set for $50) and they have the same thread pitch and inner diameter. The outer diameter is a bit less because the tube walls are thinner. This is actually nice for welding because it gives a little shoulder for the bead to sit on.

https://i.imgur.com/rpNg4Ap.jpg

https://i.imgur.com/FjRmMzi.jpg

[Aigar]

This is what I had after sand blasting. The threaded part was ok but you can see holes near the lower spring plate so take care. I will search for a one in better condition. https://m.imgur.com/a/W7lHicg

[D.Martijn]

Thanks for the feedback guys

Does any one know how thick the upper part is at the threads?
I'm considering making a new section at work on the lathe, cutting the thinned out section off and welding the new threaded piece onto the existing tube

[ForcedFirebird]

2" OD by .120" wall DOM works damn-near perfect (slightly smaller OD than the stock tubing, be aware when welding). The threads are 48mmx1.5mm. I bought a tap for it, but you will be able to thread that easily on a lathe.

[D.Martijn]

2" OD by .120" wall DOM works damn-near perfect (slightly smaller OD than the stock tubing, be aware when welding). The threads are 48mmx1.5mm. I bought a tap for it, but you will be able to thread that easily on a lathe.

Thanks for the info!
Would you butt weld the new tube onto the existing one or overlap a section?

[ForcedFirebird]

Usually butt weld them unless they are getting coil overs. Then you can sleeve it in the same spot the new perch will be. Never had a failure with a good butt weld though.

[audiquattrot]

can't believe you were able to remove the shocks from that.


Mine are a bit rusty/scaling, so I have these coming in the mail today. Seller said they have less than 2K miles on them......scored big on these and come w OEM tie rods as well!


if anyone is interested in my old housings, i'll have them for sale once I swap them out with these.

these are the new/used ones I got.

[D.Martijn]

can't believe you were able to remove the shocks from that.

I know right! Although one of the shocks leaked oil so there wasn't really any rust welding going on or at least nog much. The other one was VERY dry, can't believe I was able to get that one apart too.

Since my first post, I found a guy locally who cut rwd E30 51mm struts to fit coilovers. So I don't have to make new sleeves at work. Saves me some time to do other stuff :)