Convertible top pump fluid question
#8
Dexron dates back to at least 1967 for GM in transmissions.according to this article. https://www.hemmings.com/blog/2015/0...manufacturers/
Gm started using it at least by 2001 with TSB's retro active for use back to at least 1993 models with convertable tops.
#9
The 69 Fisher Body Service Manual says Hydraulic fluid or Type "A" or Dexron transmission fluid.
I have disassembled the entire system and will flush the lines and the pump. Both lift cylinders are new. One was installed and the system tested and failed so it will contain a small residual amount of hydraulic fluid and brake fluid mix. The second new lift cylinder was bought today.
Thanks to all who responded. I plan to reload the system with Dexron.
I have disassembled the entire system and will flush the lines and the pump. Both lift cylinders are new. One was installed and the system tested and failed so it will contain a small residual amount of hydraulic fluid and brake fluid mix. The second new lift cylinder was bought today.
Thanks to all who responded. I plan to reload the system with Dexron.
Last edited by Bitburger; June 12th, 2019 at 02:57 PM.
#10
The main issue with brake fluid is that it draws moisture and will corrode cylinders and shafts and rune seals. My car originally had brake fluid and my cylinders were damaged beyond repair after it sat a few years. If you have any questions about your system you can give Hydro- E- Electric a call, good folk and very knowledgeable.... Tedd
#11
As Tedd suggested brake fluid draws moisture. The primary reason brake fluid draws moisture is because brake fluid more closely resembles radiator coolant. The primary constituent of brake fluid is glycol - which is a derivative of ETOH (ethanol) i.e. polyethylene glycol, diethylene glycol, triethylene glycol, etc. Many variants of glycol comprise the various DOT formulas of brake fluid. Since they are derivatives of ETOH, they will readily absorb moisture. Brake fluids contain no petroleum. Transmission fluid on the other hand is petroleum based.
#12
I know, brake fluid is hygroscopic and can be quite destructive over the long run. I'm just trying to learn what year GM figured this out and stopped using it as factory fill in convertible top cylinders.
#13
Ive always heard and used transmission fluid, I bought new pump and cylinders and they recommend brake fluid and give an extended warranty using brake fluid, after reading and finding the information that brake fluid draws in moisture I am going to opt to stick with the transmission fluid it has always worked.
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