How-To: Remove/Replace Brake Fluid Reservoirs
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 1,219
Likes: 820
From: Bay Area, CA
How-To: Remove/Replace Brake Fluid Reservoirs
Difficulty is 2/10. It's easier than an oil change and you DON'T need to remove or bench bleed the master cylinder or even bleed your system afterwards.
1. Purchase x1 500mL bottle of brake fluid. The GM part number for the brake reservoir is 22968944 which is around $50. It includes everything you need (reservoir, x2 grommets, fluid level sensor and retention pin.
2. Unscrew the brake fluid reservoir cap. Use a turkey baster to remove as much of the brake fluid from the reservoir as possible. Only a small amount will be left in the reservoir afterwards, so spillage will be minimal when taking off the reservoir.
3. Unplug the fluid level sensor connector. Use a small screwdriver to release the tab.
4. Use a 5mm socket to remove the retention pin. You'll need a small 1/4" ratchet and 4-6" extension. Instead of being press fit in like most reservoirs it's actually threaded.
5. Carefully pull the reservoir out. It's only being held onto the master cylinder with two barbs with rubber grommets on them. If it doesn't pop right off, tilt it to one side and slowly shimmy it out.
6. This is what you will see now. DO NOT siphon out the brake fluid from the two openings, leave it alone. Be very careful not to spill it. Very carefully remove the x2 rubber grommets, a small pair of pliers works perfectly. Carefully inserts the x2 new rubber grommets.
7. Install the new reservoir. It requires a bit of muscle to push down.
8. Use the 5mm socket to install the new retention pin and plug in the sensor.
9. Pour in new brake fluid and fill it the MAX line. It'll be about 375mL or 80% of the bottle. Screw on the cap, pump the brakes and you're done!
1. Purchase x1 500mL bottle of brake fluid. The GM part number for the brake reservoir is 22968944 which is around $50. It includes everything you need (reservoir, x2 grommets, fluid level sensor and retention pin.
2. Unscrew the brake fluid reservoir cap. Use a turkey baster to remove as much of the brake fluid from the reservoir as possible. Only a small amount will be left in the reservoir afterwards, so spillage will be minimal when taking off the reservoir.
3. Unplug the fluid level sensor connector. Use a small screwdriver to release the tab.
4. Use a 5mm socket to remove the retention pin. You'll need a small 1/4" ratchet and 4-6" extension. Instead of being press fit in like most reservoirs it's actually threaded.
5. Carefully pull the reservoir out. It's only being held onto the master cylinder with two barbs with rubber grommets on them. If it doesn't pop right off, tilt it to one side and slowly shimmy it out.
6. This is what you will see now. DO NOT siphon out the brake fluid from the two openings, leave it alone. Be very careful not to spill it. Very carefully remove the x2 rubber grommets, a small pair of pliers works perfectly. Carefully inserts the x2 new rubber grommets.
7. Install the new reservoir. It requires a bit of muscle to push down.
8. Use the 5mm socket to install the new retention pin and plug in the sensor.
9. Pour in new brake fluid and fill it the MAX line. It'll be about 375mL or 80% of the bottle. Screw on the cap, pump the brakes and you're done!
Last edited by Pineapple; Jul 21, 2018 at 12:48 AM.
Advanced
Joined: Dec 2016
Posts: 69
Likes: 15
From: Mountain View California
Wouldn't steps #6 and #7 introduce air into the system? I'm assuming oil level will fall when the rubber grommets are pulled out in step #6. Is there still enough fluid to keep the air out?
Thanks for the detailed write up!
Thanks for the detailed write up!
Last edited by TumblingPanda; Jul 22, 2018 at 02:59 PM.
Melting Slicks
Joined: Feb 2002
Posts: 2,479
Likes: 17
From: Miami Fl
Reservoir
is there a separation in the c7!fluid reservoir like there was in the later c6 models that prevented removal of the old fluid from the top? BTE HOW IS one supposed to get all the fluid out of those c6s with the chamber separation?
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 1,219
Likes: 820
From: Bay Area, CA
There is still enough fluid in the 2 openings even after you pull out the grommets. You have a good 0.75” of fluid level left in the opening beforvyou start to introduce air into the system.
Yes, the C7 reservoir also uses a chambered design. You will not be able to siphon all the fluid out but the amount of fluid left in there really isn’t a lot. A towel wrapped around underneath the reservoir soaked up all the remaining fluid that came out..
Yes, the C7 reservoir also uses a chambered design. You will not be able to siphon all the fluid out but the amount of fluid left in there really isn’t a lot. A towel wrapped around underneath the reservoir soaked up all the remaining fluid that came out..
