C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

Flush Clutch Fluid in my 89?

 
Old 04-11-2019, 05:12 PM
  #1  
Ruger72
CF Member
Support Corvetteforum!
Thread Starter
 
Ruger72's Avatar
 
Member Since: May 2017
Location: Temecula CA
Posts: 84
Likes: 0
Recieved 1 Like on 1 Post
Default Flush Clutch Fluid in my 89?

Hey guys, so the only thing left on my Vette that has not been touched is my hydraulic Clutch fluid. My car has 31,500 miles on it and of course has the ZF 6-speed. Shifts and drives perfectly. I did open up the master cylinder reservoir and it is full. Fluid looks good. I stuck a Popsicle stick down into it and just got a little swirl of darker fluid on the bottom of the reservoir. The master cylinder itself is a little rusty looking. I am almost afraid to mess with it since everything is working fine. Do I want to flush the clutch fluid or leave it alone? If I do flush it should I just replace the master cylinder since it is 30yrs old? Any input would be appreciated.
Ruger72 is offline  
Old 04-11-2019, 06:08 PM
  #2  
DGXR
CF Senior Member
 
DGXR's Avatar
 
Member Since: May 2013
Location: Sacramento California
Posts: 2,023
Recieved 172 Likes on 160 Posts
Default

Fresh fluids are always a good idea. I am surprised that your fluid looks as good as you describe, considering the age of the system. But then, how long have you owned the car? Do you have any documentation stating if/when the clutch hydraulic system was serviced? If your fluid is still clear or mostly clear, and you recently acquired the car, I would guess that the previous owner has serviced it.

I would suck all the fluid out with a turkey baster or other siphoning method, definitely avoiding any spills on the paint. Then take a clean rag and wipe the sediment from the bottom of the reservoir. Refill with clean fluid and bleed the system through a few times, keeping a very close eye on the reservoir and topping it off -- it is small and quickly goes empty. Most people use DOT 3/4 brake fluid in their clutches but I've heard of some using power steering fluid or transmission fluid as as substitute. I suggest DOT 3/4 brake fluid.
DGXR is offline  
Old 04-14-2019, 04:09 PM
  #3  
mtwoolford
CF Senior Member
 
Member Since: Jan 2009
Location: folsom california
Posts: 3,223
Recieved 124 Likes on 119 Posts
Default

Originally Posted by DGXR View Post
Most people use DOT 3/4 brake fluid in their clutches but I've heard of some using power steering fluid or transmission fluid as as substitute. I suggest DOT 3/4 brake fluid.
Dot 5 silicon based brake fluid; it won't attack paint, it preserves seals and doesn't attract and absorb moisture. I use it in my system; I'd use it in the brake system too except that it's too viscous for an ABS system; I use it in all non ABS brake systems.
mtwoolford is offline  
Old 04-14-2019, 05:40 PM
  #4  
65Z01
CF Senior Member
 
65Z01's Avatar
 
Member Since: Dec 2000
Location: SE NY
Posts: 81,992
Likes: 0
Recieved 95 Likes on 89 Posts
Cruise-In II Veteran
Default

My '89's clutch calls for Dot 3 fluid right on the reservoir cap.
65Z01 is offline  

Thread Tools
Search this Thread
Sponsored Ads
Vendor Directory

Contact Us - About Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: