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ATF and the older truck

I’ve got a recently purchased 1975 K10 Chevy pickup. The transmission was low, got the wrong input, dumped half a bottle of ATF into the power steering.

I’ve driven it to work and back since then: steering is still fine: the wheels turn, no ugly cloud of smoke or ‘bad noises’ coming out of the motor.

‘The internets’ claim that for an older car ‘this is fine’ and ‘I do it all the time’.

But anonymous guys on the internet aren’t enough - I need anonymous guys from the Car Talk forum to assure me that I’m not going to melt the power steering.

You should be fine. Most (non-Honda) power steering systems use ATF fluid.

Does your truck have an owner’s manual? If not, the correct fluid type should be written on the top of the lid to the power steering fluid reservoir under the hood.

Both PSF and ATF are just hydraulic fluids. Many cars these days specifically do use ATF - as in that’s what you’re supposed to do. My Ford’s PSF, for example, is Mercon transmission fluid.

But if it bothers you, just suck the reservoir dry with a turkey baster or something and add whatever PSF you think you should. So that a few times after driving some & you’ll have mostly new PSF. Personally, I wouldn’t bother.

My old chevy is a 79.
Same fluid in the trans and the p/s, fka DexronIII

Your 1975 GM P.S. system will be FINE with Dexron transmission fluid. That was the factory fill…

Agree with the others. ATF can be used in place of power steering fluid on this truck, and many other older domestics.

Agree; the power steering fluid in my Nissan was low and I went to the DEALER, who sold me a quart of ATF, which is what they use. The dealer does not carry Nissan ATF. I don’t need a quart, but can top up the transmission should it get a little low.

I don’t have the owner’s manual, did buy the Haynes for it. That’s how I knew I got the wrong one.

“If not, the correct fluid type should be written on the top of the lid to the power steering fluid reservoir under the hood.”

It doesn’t even say it’s for the power steering. Just a cap with the words ‘fill’ or something like that. I have no idea if it came from Chevy like this or if it was a good-old-boy addition.

The latter is likely - the tailgate is made of 2x4s.