Automatic transmission constantly goes in and out of overdrive

Tiny
FREEBUSINESSES
  • MEMBER
  • 2003 BMW X5
  • 4.4L
  • V8
  • 4WD
  • AUTOMATIC
  • 180,000 MILES
I have an issue which is more annoying than a problem. While just trying to maintain speed at range of forty to sixty mph, the rpm is constantly going up and down 200 rpm's as if pulsating consistently, not erratically. It appears only to happen in fifth gear which makes me suspect the lock up converter is issue. In sport mode I put in fourth at same speeds and no issue, only in fifth.

No codes of any kind, just changed transmission filter and fluid and no signs of burned fluid or any evident sludge in pan. Was brown, but it was changed about 90,000 miles ago, so I suspect this would be normal. Now here is another strange issue, when shifting from third to fourth under no only slight acceleration it shudders for a second, as if slipping, but never in sport mode or under regular acceleration. Do not know if problem is connected, but thought I would mention it. Runs perfect otherwise, so any suggestions?
Do you
have the same problem?
Yes
No
Monday, November 13th, 2017 AT 7:58 AM

3 Replies

Tiny
JACOBANDNICKOLAS
  • EXPERT
It could be a few things. What you mentioned could be an issue or the torque converter clutch may be going bad. If you brought the vehicle to me, I would hook up a live data scanner and focus on the TCC to determine if it is functioning properly or there is a slippage issue being caused by it (the 200 rpm variances). If the clutch is not being signaled on and off but continues to go on and off, suspect it is the problem.

Great vehicle, so I understand why it is frustrating.
Was this
answer
helpful?
Yes
No
+1
Monday, November 13th, 2017 AT 5:51 PM
Tiny
FREEBUSINESSES
  • MEMBER
Thanks, the strange thing with this is that it is so consistent, so if it was slipping in fifth, it would be a case of rpm going up with no speed increase, as in, slipping, but this is not the case, the transmission is fully engaged, no slipping is evident, so if this can be diagnosed with diagnostic equipment, what type, the systems BMW has, or independents may have?
Was this
answer
helpful?
Yes
No
Monday, November 13th, 2017 AT 6:12 PM
Tiny
JACOBANDNICKOLAS
  • EXPERT
Most independents have what I call generic scanners. They are good, but German vehicles are a bit on the finicky side. With a BMW, you could give an independent a shot. If they have a good Snap-on type scanner, it should do the trick. If not, I recommend one made for BMW's.
Was this
answer
helpful?
Yes
No
-1
Tuesday, November 14th, 2017 AT 6:55 PM

Please login or register to post a reply.

Recommended Guides