I replaced my bolster resovoir now what oil couldnt find anything on google or ont he pump its self. Ive heard 5-30 works. But can I just put drive oil in there.

nobody knows what kind of oil they put in those?

well... i certainly don't have any factual information to offer you but i will say that rubber seals are sensitive to what they are exposed to... so you really don't want to just go throwing something in there that will just make a mess in a short time... isn't there any sort of mfg label anywhere that gives you an idea of someone to call and ask or does it smell or feel like anything you recognize ? if i had to hazard a GUESS and i emphsize GUESS i would expect it to be a hydraulic oil ... similar to what you put in a hydraulic jack...

Thats what I was thinking. The old fluid was redish. I looked on the pump and didnt say. The pump looks about the same as a drive pump. I beleive the pumps are keefhoffer(major misspelling)

[QUOTE=soldier4402;3684433]Thats what I was thinking. The old fluid was redish. I looked on the pump and didnt say. The pump looks about the same as a drive pump. I beleive the pumps are keefhoffer(major misspelling)[/QUOTE

my drive pumps used motor oil, just as you suggest in your first post. i didn't realize you had drive pumps doing the work.. i finally had to call merc directly to find that out. i had been " advised" to use every fluid there was from ATF to gear oil but the stuff that WAS in mine was clear and NOT motor oil... but then again the seals didn't last long either. when i did what merc said it was a " forever fix" . if you have merc pumps, i would call merc w/ the part numbers and see what they say.

i know this is hard to beleive,but i agree with steve,i think you would be safe in useing 30w motor oil.

I would use a mineral based oil, no synthetic.

Beleive it or not fork oil for a motorcycle will work perfectly. It has all the necessary additive for anti-wear and rust and it is available in a bunch of different weights.

Personally I think 30 is too heavy. I thinking a 5W or a 10W (or a blend of them) would be just about perfect.

Ken

i would use what the guys that manufactured the pumps say to use... which is 10-30 motor oil... seems to me they might have some insight into what is actuallt correct..but hell... what do they know...

ATF is always a safe choice