Green coolant leak coming from driver side behind rear tire

[Effduration]

or coolant dye and glasses/flashlight from Amazon. Put one half a small bottle in the coolant system...You will find your leak.

[Meestahbig]

I drove about 80 miles today. No warning of low coolant, so if indeed a leak I guess it's very small still. I'll pressure test and go from there. Spare bottle of coolant in the truck always, anyway. Along with oil and trans fluid for an occasional power steering top up, but that issue seems resolved, lol.

[80stech]

The nice thing about the pressure tester is that you can test the system at a higher than operating pressure which gives you a bit of a window of confidence that nothing is close to blowing out on you!

[Meestahbig]

Anyone have a good cheap kit that fits the e53 3.0? I looked at a few and couldn't decide.

[Fifty150hs]

Originally Posted by Salty B.

Yikes. Hope it's an easy fix!

What's the difference between the blue and green coolant anyway? I mean other than the price!

Not an easy fix. Sounds like the one or both of the plastic pipes under the intake are probably leaking. When I changed mine at around 250k miles, part of the pipe that inserts into the head was gone. The pipe has two o rings, this only had one because the part the o ring sits on was gone.

The blue coolant is BMW coolant and expensive. I've been running green for a long, long time with no ill effects.

[Fifty150hs]

Originally Posted by Themoog

Brake fluid

Brake fluid isn't green. Or blue for that matter.

[Meestahbig]

So far haven't seen any further indication if a leak. So weird.

I def need to man up and learn how to pull the intake manifold from these cars.

I think it's just a matter of doing it once or twice and then well, it's not too hard!

[wpoll]

Originally Posted by Fifty150hs

Brake fluid isn't green. Or blue for that matter.

The brake fluid in my E53 is currently blue.

Bendix DOT4 fluid was dyed blue for many years. They have changed to the regular straw-coloured dye now - and I'm due a flush, so out with the blue...

I like to change fluid to a differnt colour when flushing - makes it easier to see when the fresh fluid is pushed out at the bleed nipple. Getting hard to do that now, since pretty much all DOT4 is now straw coloured.

[Fifty150hs]

Originally Posted by Meestahbig

So far haven't seen any further indication if a leak. So weird.

I def need to man up and learn how to pull the intake manifold from these cars.

I think it's just a matter of doing it once or twice and then well, it's not too hard!

Actually not too difficult a job. Trickiest thing is getting the nut off the support bracket for the manifold where it attaches to the block. I use an extra long extension to get a socket on it. It does get easier the more times you do it.

[Meestahbig]

My brake fluid reservoir is at the max! And I can see it's reddish. It's definitely was the color of my generic Prestone coolant which suits the car just fine.