4hp22eh

[mamilapon]

OK First thing in the morning,back it out of the garage on to the driveway(fairly level).I sit there for a minute foot on brakes and in reverse gear.Sounds like a pump is sucking on nothing coming from the gearbox. Put it in drive, beautiful no noise.put it back in reverse after a drive, no noise!! What could it be???? Anybody experienced that?

[aston_jag_tech]

Sounds like the fluid was flowing the opposite way. Just like how toilets flush the wrong way right?? Just kidding pal.....Hows the fluid when cold? Have you had any tranny work before??

[mamilapon]

Nope, no tranny work as far as I know. Bought it 2 years ago.serviced it with new filter and fluid soon after I got it.Reverse gear can be a little rough on application but box hasn't caused any problems.

[shogun]

First thing always: check fluid level.

Maybe the valve body dirty and the balls have a problem to go to the right place.

Had a similar problem some months ago on a Alpina B12 5.0 E32.
We did the valve body with new balls, cleaned all and the tranny runs like a charm now.
Bought the parts from the U.K.
But Kirt Koeller has them too. Not very difficult.
The 4HP22 and the one from the Alpina 4HP24 are not very different, torque converter is larger on the V12 and the Alpina has no slip from second gear, but that is only a valve function respect. programming of the control unit.
To get an idea about the job, see my website under valve body rebuild, but that is a 5HP30, so just for genral info.

[mamilapon]

Will do shogun