E46Fanatics - View Single Post - SMG Pump Failure Thread
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Old 08-31-2012, 11:32 PM   #201
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Join Date: Jul 2011
Location: PDX
Posts: 588
My Ride: 2005 330xi
Anybody else notice that the age of a lot of the cars posting SMG issues, is similar to the age the Vanos issues occur?

Has anybody tried to add external cooling to the hydraulic pump?
Most failures in any hydraulic systems are internal heat related.

Has anybody tried adding a fan and duct to cool the hydraulic system area?
(Think break duct... ) This would help your sensors as well.

I really believe there is almost no way to over-cool hydraulics. All the automatic
trans cars I've owned have gotten a setrab cooler to replace the lame factory ones.
Usually close to the size of the car radiator. Now I know the hydraulics on the SMG
trans are a fairly small closed system. This means heat is going to happen quickly.
Its possible the on actuation in high heat conditions your actually getting bubbles in the fluid.

Anybody ever put a gauge on the system to watch the hydro temps? Most hydraulic
fluid is going to have issues above 250 degrees.


Last edited by dwtaylorpdx; 08-31-2012 at 11:33 PM.
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