oil to be put in shock inserts?

[bgbmxer]

got new shocks for my rabbit since the old ones are shot. apparently im supposed to fill the body up with oil but when i took it appart most of the oil was gone anyway. is the oil for cooling? is it needed more importantly?

[8v-of-fury]

The oil is there as a backfill. And takes away the pocket of air between the insert and the housing. An air pocket that if left will super heat the strut and it will fail in short order.

The oil allows heat dissipation from the strut, to the other metal components of the suspension to act as a giant heat sink. Very effective at keeping the struts cool.

[bgbmxer]

The oil is there as a backfill. And takes away the pocket of air between the insert and the housing. An air pocket that if left will super heat the strut and it will fail in short order.

The oil allows heat dissipation from the strut, to the other metal components of the suspension to act as a giant heat sink. Very effective at keeping the struts cool.

what kind? how much? and what seals it in there?

[8v-of-fury]

I am on my phone at work, so I can't easily check.. But a google search of "backfilling struts with oil" should do well in helping you out.

[bgbmxer]

I am on my phone at work, so I can't easily check.. But a google search of "backfilling struts with oil" should do well in helping you out.

found the thread with you talking about struts and backfilling them. i didnt know that backfilling was the term when i was trying to search earlier so i posted. so about four ounces? and nothing was mentioned about sealing it. does it just seal from the nut jamming down on the insert? might put some soft set pipe dope on the threads and such to stop leakage.

[rabbitman]

I doubt anything actually seals it in there, I think when I did mine I filled it enough that it over flowed when dropped the shock in. Probably when the shock heats up it'll expand and push out somewhere.

[maxfax]

 4 oz give or take sounds right..  The nut jamming down is supposed to seal them, but typically does not make a perfect seal... Pipe dope would probably help with sealing, and help keep the nut from rusting tighter than a #$*() in there..  Just make sure you don;t use a pipe dope that sets up hard.. Makes removing the nut at a later date a PITA..  Just about any sort of oil would do the deed..

Personally I usually use ATF since I always have plenty..  Dump some in the housing, drop the insert in till it pushes the excess out..  Clean up the oil around the threads, put some RTV on the nut, and crank'er together..

[CRSMP5]

be very carefull with this idea... the oil will hydrolock the insert not allowing it to seat in all the way... and for 25+ years have NEVER done this with no issues at all in longetivity/life..

[rabbitman]

be very carefull with this idea... the oil will hydrolock the insert not allowing it to seat in all the way... and for 25+ years have NEVER done this with no issues at all in longetivity/life..

I thing there's enough room for the oil to go around the shock.

[Luckypabst]

I regret not putting oil in mine... I've ruined two Bilstein HDs in short order on high speed dirt roads in my Caddy. One locked up, fully extended, the other did the same but started working again after it cooled off.

Chris

[maxfax]

Every one I have done the oil squirts right up around the shock in the housing.. Plop an insert in the housing dry, the clearance is surprising..  I would recommend a light oil though, it will make it go much easier..   

One other reason I have found for putting oil in there, and I'm sure this was not the engineers intent, but moisture has an amazing way of finding its way everywhere..  Ever try to get the insert out of the housing when the darned thing is full of water and rust??     The other strut on this particular car was pushed up from freezing and stripped the threads of the retainer nut.. It had some interesting driving characteristics...

[bgbmxer]

4 oz give or take sounds right..  The nut jamming down is supposed to seal them, but typically does not make a perfect seal... Pipe dope would probably help with sealing, and help keep the nut from rusting tighter than a #$*() in there..  Just make sure you don;t use a pipe dope that sets up hard.. Makes removing the nut at a later date a PITA..  Just about any sort of oil would do the deed..

Personally I usually use ATF since I always have plenty..  Dump some in the housing, drop the insert in till it pushes the excess out..  Clean up the oil around the threads, put some RTV on the nut, and crank'er together..

hense why i said soft setting dope. i work in the plumbing field and rarely ever use dope that sets up hard ever. four ounces sounds like it wouldnt fill up the housing the whole way leaving room for expansion anyway. guess we will see.

[bgbmxer]

all the oil does is make heat transfer to the strut housing which transefers heat out. if it was a normal setup this wouldnt be needed lol

[maxfax]

might put some soft set pipe dope on the threads and such to stop leakage.

Missed that part..  I hate the hard dope.. Guaranteed if I use it on something, I gotta take it back apart in short order..  

Insert Quote
all the oil does is make heat transfer to the strut housing which transefers heat out. if it was a normal setup this wouldnt be needed lol

The original struts from the factory are more more or less like a normal strut.. The housing is full of oil, and is the outer shell for the strut.. It's the replacements that mix things up a little with already having their own shell..

 I'd be willing to bet VW didn't come up with this idea originally..  As like all the other manufacturers, they don't intend for their cars to still be on the road after 500K miles and 20 years.. Chances are good that someone in the aftermarket field came up with the idea "hey, you could just pull the old guts outta the strut and we could make an insert to fit in there for a much cheaper replacement part"..  Just a hunch though..