2002 XC70 Transmission question

mark99tj · Post by **mark99tj** » 28 Dec 2018, 18:26

2002 XC70 with 100,000 miles.

I bought the car 2 months ago and the bare minimum maintenance was done. I have changed out the transmission fluid 3 times prior to today. When I got it it did have a hard shift between 2nd and 3rd which went away with fluid change. With each change (over 3,000 miles) the fluid is looking better and better.

Tonight I changed it the 4th time and also did the B4 servo. What a pain by the way.....

After reassembly I did a test drive. About 5 miles mostly highway. It seems to shift much smoother now, especially from second to third. However, when I first put it in drive, it doesn’t engage right away and about half the time it feels like it engages twice— the second almost like a rev of the engine but my foot is still on the brakes.

Did I do something wrong with the servo? Is it something else that just happened to occur now? I don’t believe in coincidences but if it was the servo I would have expected it to shift differently between second and third.

Thanks for the help....

Post by **vtl** » 30 Dec 2018, 07:20

What kind of ATF did you use? It generally does double drive engagement when linear pressure is low.

mark99tj · Post by **mark99tj** » 30 Dec 2018, 07:47

Idemitsu From FCP.

The double engagement seems to have resolved itself but it is still hard to engage drive when warm.
It may be time to do a gibbons flush.

Georgeandkira · Post by **Georgeandkira** » 30 Dec 2018, 08:13

My '02 did the same including "double bumping" into D.
It had been addressed by the original owner at the dealership. The fluid was perfectly clean when I bought it.
A TCM download (Volvo pn 30677036) GREATLY improved things.
That was over 10 years ago so the pn may have been superseded.
The addition of the prescribed dose of LubeGard (red bottle) eliminated MUCH MORE that half of any remaining shifting woes.
I eschew snake oils but LG came highly recommended by members of another board.
My suggestion is to get your fluid as clean as you can and include LG.

The purchaser of my car (@ 198K) expressed amazement at how well it shifted.

Post by **SuperHerman** » 30 Dec 2018, 13:16

Being a 2002, it is possible you have one of the "no letter" valve bodies. At some point near 2002, they upgraded the the internals slightly and I think they may have changed the solenoid design. Only real way to know is to open it up and look. Problem is once you open it up, you may as well replace the solenoids and/or do a TransGo rebuild of the solenoids and valve body.

Your description matches a sticking solenoid(s) being the culprit. Plenty of threads to read which explain the problem and the possible fixes.

Post by **oragex** » 30 Dec 2018, 14:58

That D engagement issue happened after replacing the servo cover? Was the cover faulty? Any reset done by the main dealer? What fluid was used?

I doubt the b4 is related to D engagement. However, if you google it, many 2002 xc had problems with delayed D engagement. My bet would be is related to the fresh fluid and valve body wear. You may try to have the dealer disable the neutral stop function and reset the fluid counter, but I woould ask not to reset the adaptations because that is related to installing new vb or solenoids.

Post by **precopster** » 31 Dec 2018, 04:10

The B4 servo has one function only. The piston in front of it pushes the band clamp around the 3rd gear drum. That's why transition from 2nd to 3rd improves with the cover replacement. The piston bore behind the cover is equally important and I believe Oragex has covered this in one of his videos.

Delayed engagement is definitely a solenoid issue.