Dot 3 to Dot 4 Swap

[rednecks70]

First time doing this and read that the clutch and brakes use the same reservoir. Assuming they both need to be bled. My concern is I've got neck problems and the bleeder valve for the trans looks like its in a bad spot. Was thinking about having my mechanic bleed the trans and I would do the brakes but concerned about contamination if there not done at the same time. Thoughts?

[ZMEnow]

Originally Posted by rednecks70

First time doing this and read that the clutch and brakes use the same reservoir. Assuming they both need to be bled. My concern is I've got neck problems and the bleeder valve for the trans looks like its in a bad spot. Was thinking about having my mechanic bleed the trans and I would do the brakes but concerned about contamination if there not done at the same time. Thoughts?

You can mix the two without worries just remember to cycle the ABS unit to get the fluid out of there, and keep in mind what is in the trans slave cylinder is still Dot 4 which is a 2 year max as it will continue to pull in moisture and cause rust. NEVER mix 3/4 with Dot 5 as its silicone based. As far as bleeding the slave cylinder the bleeder is so far inside the trans its a PITA to get a socket/wrench to even with a lift, and remember unless you are using a Mity-VAC (Wouldn't do it any other way) you have to open close between brake pumps so a min of a two man opp.


That was something I did around 8 years ago was to put a Monster extended one man bleeder on and I just slip on the Mity-VAC after doing the brakes. It makes sense to put one on if you are doing a clutch or slave cylinder.


I just re-read you thread, you are going from Dot 3 to 4, so I assume that's for the brakes? unless you are planning on doing some heavy burnouts and you want to prevent the clutch peddle from going to the floor going to 4 is simple just turkey baster or Mity -VAC out master cylinder and start the bleeding process. RR/LF/LR/RF.