E30 Tranny Cooler Lines - BMW Forum

JoeMadoo · 01-07-2006, 12:30 PM

I just did a Engine/Tranny Swap from an 87 528e to an 86 325es. Everything went great except for the Upper Tranny Cooler Line. The Hole at the top of the Transmission is threaded on the inside instead of the outside. I'm sick of these cooler lines anyway, could i just bypass them or plug them up somehow?

gsrboy171 · 01-07-2006, 03:43 PM

is it auto?

JoeMadoo · 01-07-2006, 05:33 PM

It's an Automatic. I don't think they made cooler lines for 5 speeds.

Starmavin · 01-07-2006, 06:58 PM

You cannot plug the cooler lines. A word to the wise: Heat is the #1 killer of automatic transmissions. The radiator cooler is best, go to a parts house and get an adapter. You can bypass the radiator cooler for an aftermarket trans cooler. But I highly advise that you don't use these coolers as a total replacment, they are used to assist the rad cooler under heavy use. Keep in mind that you can have the fluid "too cool" making your trans shift slugish in cold weather causing premature clutch wear.

JoeMadoo · 01-07-2006, 10:35 PM

Would it be ok to bypass them just for the winter time? This car only goes about 8 miles at a time (with some spirited driving inbetween).

Starmavin · 01-08-2006, 02:36 PM

If your rad has an internal threaded fitting you should be able to go to a parts house and find a short steel line that will fit your rad, make a bend in it and cut off the head and the neck of your cooler line and splice with a rubber hose and two hose clamps.

JoeMadoo · 01-09-2006, 12:22 AM

Rubber dosent work for ATF, It will turn the hose into sludge... I know from experiance. I'm thinking about cutting the original steel braided lines and some old ones i have and joining them together with a piece of copper pipe.

luckycat · 01-09-2006, 07:26 AM

Try Nylon re-enforced vinyl tubing, it won't degrade like rubber.
(Lowes-Home depot)

JoeMadoo · 01-09-2006, 10:47 AM

Ok, I'll give that a shot today, thanks alot.

Starmavin · 01-09-2006, 08:19 PM

Quote:

Originally Posted by JoeMadoo

Would it be ok to bypass them just for the winter time? This car only goes about 8 miles at a time (with some spirited driving inbetween).

If you were temped to bypass the cooler at all, the rubber lines would have lasted longer than the transmission. A compression or a double flare fitting would work better in this application if you wanted to make this a permanent fix.