Correct power steering fluid to use in an early 71 Corvette Small block ???

[Tom S.]

I seem to have a consistent seepage/leak on my power steering control valve that annoys me to death. I have changed the p/s control valve 2-3 times already (all original GM valves that were rebuilt by two separate suppliers) during the past 2 years and it seems ok for awhile and then the control valve starts with a small drip again after a few months. Now a notice a small drip coming from the p/s piston (which is the original to the car from 1970). It is just annoying to me and I want it gone! Some of the research that I have done says that there might still be contaminants in the rest of the system fluid that eventually have made there way to the seals in the rebuilt control valves that I replaced, thus causing them to leak. That kinda makes sense to me too. So I have decided that to eliminate the chance for all possible contamination, and that I should replace everything and start from fresh. Re-manufactured original GM p/s pump and GM control valve from Lonestar Calipers in TX and I have an NOS GM p/s piston along with (4) NOS GM hoses. Now, my question is ---- What is the best choice for power steering fluid? I believe than originally GM called for the use of Dexron III fluid. I see that now they make a synthetic Dexron fluid also. I am leaning towards what GM originally called for and staying away from the new synthetic. Any thoughts on what is the best fluid for me to use? Any ideas or in sight would be appreciated. Thanks, Tom

[Terry M.]

Re: Correct power steering fluid to use in an early 71 Corvette Small block ???

I seem to have a consistent seepage/leak on my power steering control valve that annoys me to death. I have changed the p/s control valve 2-3 times already (all original GM valves that were rebuilt by two separate suppliers) during the past 2 years and it seems ok for awhile and then the control valve starts with a small drip again after a few months. Now a notice a small drip coming from the p/s piston (which is the original to the car from 1970). It is just annoying to me and I want it gone! Some of the research that I have done says that there might still be contaminants in the rest of the system fluid that eventually have made there way to the seals in the rebuilt control valves that I replaced, thus causing them to leak. That kinda makes sense to me too. So I have decided that to eliminate the chance for all possible contamination, and that I should replace everything and start from fresh. Re-manufactured original GM p/s pump and GM control valve from Lonestar Calipers in TX and I have an NOS GM p/s piston along with (4) NOS GM hoses. Now, my question is ---- What is the best choice for power steering fluid? I believe than originally GM called for the use of Dexron III fluid. I see that now they make a synthetic Dexron fluid also. I am leaning towards what GM originally called for and staying away from the new synthetic. Any thoughts on what is the best fluid for me to use? Any ideas or in sight would be appreciated. Thanks, Tom

No advice on fluid, but I strongly urge the installation of a PS fluid filter. I am not sure there is room for one on Corvette as my experience was on a much larger vehicle, but if I were you I would look into the filter. They are not too large so look into it.

[Joe L.]

Re: Correct power steering fluid to use in an early 71 Corvette Small block ???

I seem to have a consistent seepage/leak on my power steering control valve that annoys me to death. I have changed the p/s control valve 2-3 times already (all original GM valves that were rebuilt by two separate suppliers) during the past 2 years and it seems ok for awhile and then the control valve starts with a small drip again after a few months. Now a notice a small drip coming from the p/s piston (which is the original to the car from 1970). It is just annoying to me and I want it gone! Some of the research that I have done says that there might still be contaminants in the rest of the system fluid that eventually have made there way to the seals in the rebuilt control valves that I replaced, thus causing them to leak. That kinda makes sense to me too. So I have decided that to eliminate the chance for all possible contamination, and that I should replace everything and start from fresh. Re-manufactured original GM p/s pump and GM control valve from Lonestar Calipers in TX and I have an NOS GM p/s piston along with (4) NOS GM hoses. Now, my question is ---- What is the best choice for power steering fluid? I believe than originally GM called for the use of Dexron III fluid. I see that now they make a synthetic Dexron fluid also. I am leaning towards what GM originally called for and staying away from the new synthetic. Any thoughts on what is the best fluid for me to use? Any ideas or in sight would be appreciated. Thanks, Tom

Tom-------



If you want to use an original formulation power steering fluid, use GM #19329448, aka ACDelco 10-5073. If you decide to use a partially synthetic power steering fluid (a fluid labeled "cold climate" but suitable for all climates) use GM #12345867, aka ACDelco 10-5044. For me, I use the 12345867.

By the way, after you install all new system components, flush the system, and begin using it on the road, in a few months you'll have another leak. Practically guaranteed.

[Mark E.]

Re: Correct power steering fluid to use in an early 71 Corvette Small block ???

Tom-------

By the way, after you install all new system components, flush the system, and begin using it on the road, in a few months you'll have another leak. Practically guaranteed.

But hopefully it's only a slow weep. If lucky the fluid doesn't drip onto the floor but rather just clings to the bottom of the valve until the engine starts and blows it away. It's a design feature of Corvette like hot floors and wind noise.

[Don H.]

Re: Correct power steering fluid to use in an early 71 Corvette Small block ???

I had my '65 control valve and slave cylinder rebuilt by Lonestar. After receiving them back I installed and used ATF like I have for over 20 years in this car (and longer in other cars). The control valve slowly started leaking and got worse very fast. I removed and returned it to them (5 year warranty). They called me shortly after getting them and the problem was ATF! The new rebuild kit components are not compatible with ATF, you need to use power steering fluid. They admitted the need to update their return documentation. Don H.

[Tom S.]

Re: Correct power steering fluid to use in an early 71 Corvette Small block ???

Don, Any particular brand of power steering fluid? Synthetic or just regular p/s fluid?

[Don H.]

Re: Correct power steering fluid to use in an early 71 Corvette Small block ???

Tom, I bought Valvoline power steering fluid, I'm not sure if it is synthetic or not. I think they said it didn't matter as long as it is power steering fluid. Good luck, Don H.

[Mark E.]

Re: Correct power steering fluid to use in an early 71 Corvette Small block ???

I doubt the type of ps fluid matters much.

[Tom S.]

Re: Correct power steering fluid to use in an early 71 Corvette Small block ???

I just made a quick call to Lonestar to ask them what they say and their response was "do not use ATF fluid, but to only use power steering fluid. Any name brand of power steering fluid is ok" Well, I am going to replace all the power steering components and use Vavoline power steering fluid. I guess to the true test will be after a few months of driving and see what happens (or does not happen). I'll keep you posted . Thanks to all for your input and advice. Tom