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Struts again!

565 Views 10 Replies 9 Participants Last post by  wangsman

I just manage to open my old front strut housings today (the struts inside seems original and they were only for decoration, only the springs were doing something in the suspension!).
Question : i have read (front struts replacement on atlanticz.ca) that you need to put oil in the housing.
But may be it is only for the type of struts blue was installing?
Mine are KYB GR2, and I don't see anything about putting some oil.
And If I do there is no seal on top of the strut, so the oil will be able to go out...?

thanks for your advice
280z 1978
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you are correct.the KYB replacements require NO oil to be added in the strut housing.
Thanks Coyote, I can start to put everything together now!
WHOA!!!! Yes you do need some oil in the housings between the insert and the strut housing. The reason is to tranfer heat. Without any oil, the -air gap- acts like a thermos bottle and traps the heat inside the insert. Can you say insulated? That's all a shock really is, it tranfers motion into heat. Without some way of cooling, it's going to overheat the fluid and become ineffective.

I've pulled out hundreds of "dry" ones that have gotten so hot they've burned the paint off the insert and turned the shafts blue. Probably why I was replacing them again?

Just pour some ATF or leave a little of the old oil in the housing. The nut is jamed against the top the the insert so it's not going to leak out even if you turned the car upside down. :)
If you want the cartridges to rust permanently inside the tubes, don't use oil. In addition to preventing rust, the oil transfers away heat, as noted by steves280.

This topic has been hashed endlessly in the archives and there are diehard believers in the no-oil camp. But don't listen to them, they haven't had to drill holes in the bottoms of struts and drive the old cartridges out with a punch.
I'm one of the old die-hards that THE Z DOCTOR is refering to. Basicly my experience with hundreds of Z cars from 70 -78 is IF gas replacement cartriges are to be installed then do NOT use oil. And should you insist upon using oil then use a VERY LIGHT weight oil such as MARVEL MYSTERY OIL and not any heavy motor oil. If installing hydrolic cartriges then you MUST use oil and the heaviest oil availabe would be best such as differential gear oil or tranny oil. Hope this helps you. BTW, I know for a fact that KYB will VOID the warranty if motor oil is used in the strut housing holding their gas strut cartriges. Goodluck.
I used oil. Easy to do and no problems.

There was remnants of oil when I took the old struts out. I think they were Monroe.
you're takin a chance with no oil but there are no adverse affects to adding it. i would just add some...can't harm. plus the old KYB i took out weres shot...and the bottom was solidly rusted the the strut housing...made it a bitch to get out.
To the no-oil camp:

Do not add oil.......why? Also advise as to where KYB voids warranties if oil is used.

Use light oil with gas cartridges.........why? Give a good believable reason, no mythology please.

Use heavy oil with hydraulic cartridges........why? Again, hard facts, leave off the myths and skip the anecdotes........
KYB will void the warantee? HaHa, like they would know either way.

Follow the FSM and add oil. Whether the strut is air or hydraulic, it will make heat and heat does not care how it was made. Heat will flow out better if you give it a path. Oil is a path, air is an insulator.

Also if you do not want the insert to rust in place, fill it like the FSM says.


Post Edited (Oct 5, 11:56am)
You need oil in the outer casing for heat transfer. That is it.

Motor oil works just fine. Don't worry, oil in contact with metal doesn't harm metal.
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