Transmission vibrations in 2009 Forester

I have a 09 Subaru Forester with 66k miles that vibrates like it is going over rumble strips when it up shifts from 3rd to 4th gear. It occurs under normal (not brisk) acceleration. I had the trans fluid changed at both the 30k and 60k services. I have owned this since new. It began before the 60k service. Also, sometimes the tach will increase revs during this as well. I don’t know if this next thing is related but when I once need to merge quickly into interstate traffic I gave it a good amount of throttle and the tach revs incresed but the trans did not follow with an immediate down shift. Thanks for any help.

You need to get this car to an independent trans shop a.s.a.p.
The “rumble” upon shifting to 4th gear is probably only a bad torque converter lockup mechanism, but the failure to downshift could indicate a more serious problem.

So…check your fluid level in order to make sure that it is red, non-burnt smelling, and at the proper level, and if everything is in order, then you need to go to an indy trans shop for futher diagnosis.

Do NOT go to AAMCO, Lee Myles, Cottman, Mr. Transmission, or any other chain operation unless you want to be told that you need a new/overhauled transmission–whether you really do or not.

I took the car to a very reputable independent shop. They said they found some brass in the pan when they took it off. Quoted me $2300 to rebuild it. I then picked the car back up and took it to the dealer where I gave them the information on my 60k service, whereupon they said that flushing the transmission (with BG or any similar product) was NOT what Subaru reccomends. They further said that Subaru does NOT reccomend a detergent type of flush and that the only (ie: Subaru) way to change the trans fluid at the 30 and 60k service is to just drain and refill without a flush. The service write then said in order to make sure it was not a Subaru problem was to do a trans service the correct way. $324 later I got the car back. Well…does the problem still exist? Let me say that for a while it did, but not nearly as much as before. Now 3k miles later it does not vibrate at all. WHY??? Beats me. I am dumbounded as to how the vibration problem vanished. The dealers explanation of Subaru not reccomending a detergent flush makes no sense to me, seeing as how may shops do this. Only time will tell…

@work2ride many of us responding here recommend AGAINST flushing an automatic transmission.

Drain and refill every 30K
Replace the filter every 30K
Use only the ATF called for in the owner’s manual
Do NOT use a generic multi-purpose jack of all trades ATF
Do NOT let a shop talk you into a flush, unless they’re also dropping the pan, replacing the filter and using the correct ATF

Many shops that push those flushes don’t drop the pan. Your filter does not get replaced. And many of them use generic multi purpose ATF.

In my opinion, flushes are huge profit generators for shops. They allow the shop to get the car out of the shop a lot faster, versus draining ATF, droping the pan, replacing the filter, etc.

If the brass in the pan part of this is true then you may not be out of the woods yet. Brass is bushing material and that often means internal trouble.
It would be interesting to know how dirty that pan was and just how much brass was in it; assuming it’s all true of course.

DB is correct of course and I might add that the service manager of the longest established Ford dealer in the U.S. told me a few years ago and I quote, “We haven’t dropped a transmission pan here in 15 years”. My response was that they had been doing it wrong for 15 years.