Correct Power Steering Fluid-71 280se
 

I need some advice regarding the correct type of power steering fluid I should use in my 71 280se.
My intention is to change the Hi/Low hoses, remove and clean the reservoir-anyone flushed the pump and steering gear box?
Thanks,
Turner

I, also, am curious about the use of auto trans fluid in the power steering as specified for our older cars. I had a '73 GMC motor home that GM originally filled with trans fluid in the steering box and specified to replace with the same. A few years later, they changed the recommendation, saying that auto trans fluid, with it's friction enhancers, was causing premature wear to the internal steering box parts. The manual for my '77 230 specifies auto trans fluid while the manual for my '90 300E specifies power steering fluid. Both cars have basically the same worm and roller steering box design. It is interesting that so many W123 owners experience steering box wear that requires adjustment or replacement but this complaint is heard MUCH less often on the W124 cars. MY '77 123 required adjustment at 70+K miles and later had a replacement box. Now, at 153K miles, the new box needs adjusting. My 124 has 112K miles on the original box and seems as tight as when new. Both cars driven the same way, by the same people and on basically the same roads.

it certainly calls for ATF, but like others , with the new PS fluid formualtions, would they not be better?

Mine calls for ATF too. I dont think there was such a thing as "Power steering fluid" in the 70's. I used ATF for ages. I switched to PS fluid for 1 reason: The ATF was not as viscous as PS fluid in the really cold temps and it would groan more, and it would be tougher to turn.

When I replaced it, I bled the whole system out when the pump was off (I replaced it with a newly resealed one that didn't leak). I dont know about mixing the fluids but would advise against.

Turner, If you are going that far, note this....
Does your pump squeal when turned to the left/right lock?
Does the pump leak?
If so remove disassemble, replace front shaft seal, ($3).
I take the body apart, polish the vanes and slot wheel, clean the body cavity, replace filter ($12).

result, no leaks, no squeals.

Those Vickers pump will last two lifetimes.