Front strut cartridge question

[91GPSTE]

I am doing suspension work on the GP this weekend and took out the strut cartridges. There is hydraulic oil in there. I want to drain the old oil and refill it with new stuff. Anyone knows that type it is and the capacity?

 

Before anyone asks, yes I have considered replacing the cartridges. In fact I have 2 brand new Sensatraks laying around but the originals are still good too, just need new oil.

[91lx5sp]

What you have to do is to drain some of the oil from the strut tube,not all of it and then install the new cartridges. The reason to keep some of the oil in the strut tube is to keep the new cartridge from banging around. I got this tip from a tech who use to work for GM dealership...Hope this help.

[91GPSTE]

Did you even read the question?

[R Dubya]

He's correct with that info, but all you need is motor oil, any kind will do. Easy solution to the how much question. Drain what you have in the knuckle, then replace that amount with new oil of the same quantity. The only purpose it serves is to dampen the sound of it moving around in there.

[91GPSTE]

No, the original cartridge is hydraulic so it uses hydraulic oil. It's like putting transmission fluid into the motor.

[GnatGoSplat]

I don't think anyone would know what type it is, because it's not designed to be replaced. All new Delco replacements are sealed cartridges.

 

You could probably try power steering fluid. It seems very similar.

[R Dubya]

No 91GPSTE you will be fine with motor oil. The strut cartridge is sealed and the only purpose is to keep it from banging around. You can or can't trust me if you want, but I assure you according to me doing the same thing and according to the recommendation of a SAE certified mechanic at the GM dealership I work at, you can use oil.

[GnatGoSplat]

Actually 91GPSTE was right, the factory original struts are NOT sealed, the hydraulic fluid in there is the actual hydraulic fluid used for dampening.

All the GM Delco replacements are sealed, but when these cars came off the assembly line, they used non-sealed struts. The recommendation you're talking about is when you replace a strut with a sealed unit.

 

Like I've said before, it's pretty unheard of for someone to replace that fluid while still reusing the original open struts.

[19Cutlass94]

The hydraulic oil is thicker than motor oil, thats why they use it. I would just go with the R&O hydraulic oil, that should be fine. Since theres really only a couple kinds of hydraulic oil, which I cant remember at the moment.

[AWeb80]

I took the oil out when I put in my KYB's cause they are sealed and it is pointless for the oil to be there.....I have no Banging and everything is kosher.

[94CutlassSLCoupe]

I just changed my front struts this morning (they were fucked) and I just left the oil in there just to inhibit rust/try to keep it from squeaking...athough most of it came out since the sealed struts are larger in diameter.

 

Wow does the car handle sweet now too.

[GnatGoSplat]

Just a FYI... the Monroe documentation that came with the Sensatracs I bought said to leave some of the hydraulic fluid in there for cooling. No mention of banging around or cushion. Probably doesn't make much difference though, I don't think struts get very hot.