Shocks: Houdaille shock absorber fluid

[tomlewis]

Not long ago there was a thread about retrofitting tubular shocks to a 1950 Studebaker and one of the replies mentioned that modern hydraulic jack fluid is suitable for use in Houdaille shocks. Is this correct?

I just pulled the plugs on the Houdaille shocks on my '35 Commander and the shocks were bone-dry as I suspected. I do have movement on the arms, so I'm hoping that fluid might restore function, but want to make sure I use the right stuff. Even back in the day, manufacturers of fluid claimed there was a difference between which fluid to use in Houdaille and Delco shocks.

Anybody know for sure?

Thanks. Tom

[TWChamp]

At least on the Model A Fords with Houdaille shocks, they used glycerin, which attracts moisture. These days most guys use modern hydraulic oil, but you need to clean the old stuff out first.

[unimogjohn]

I have used motorcycle front fork fluid with good results.

[garyash]

The original fluid was 90% glycerine and 10% denatured alcohol. You can flush out the old stuff with the alcohol, then refill with the correct mixture. You can use other stuff when you know the seals are compatible with the fluid. If you are not sure about compatibility, use the original stuff.

[tomlewis]

Thanks for the replies. I remember my first Model A 45 years ago called for glycerine in the shocks.

I have to confess that I didn't (don't) know what glycerine is. I've never seen containers labeled as glycerine in any auto parts stores. So I looked on eBay and discovered 18,000 listings. Apparently glycerine is a vegetable product and available in non-GMO, food grade, and Kosher certification. I've gone almost 70 years without needing any, so I highly doubt I'll buy the gallon size! Tom

[kxet]

I have seen glycerine in a drug store.

[Hallabutt]

There seems to be different grades of glycerin. Some have advised that only distilled glycerin should be used in shocks. What the difference is I don't know.

[kxet]

I found info about HOO-DIE shocks on early ford web sites,they were popular in early racers because they are adjustable, old Ferraris used them. Just Google Houdaille(HOO-DIE) and you can learn a lot. I"m sure car makers went to tubes because they were cheap throwaway things that took no maintenance. Several kinds of oil. Seem to last well.

[garyash]

You might find glycerine in a drug store or even at the grocery store. See the Wikipedia listing for glycerine.