e65 autobox revs hunting
Discussion
Car is a BMW e65 745i, 136k miles.
I've only noticed this in the first few minutes of driving from cold and it quickly disappears. When leaving for work it's not long before I hit an NSL section so always see it. When keeping a constant speed, say cruise set a 60, I noticed the revs would hunt from around 2000-2200rpm. Within 30 secs or so I'm turning on to dual carriageway, get up to speed again and the revs stay constant.
On my initial acceleration when hitting the first section of NSL, the car occasionally doesn't want to shift up into the last 2 gears and I do it manually. As above, I'm then shortly turning onto the dual carriageway and it shifts just fine.
I'd say the car can sound a bit whiney, most notable at lower speeds but as I don't have another to compare it to I'm not sure if this is typical.
Torque converter issue? The gearbox itself had a decent amount of work done to it (e65Ross's old car) less than 30k miles ago and the gearbox itself was said to be in fine condition then.
Edit 15/2/18-
I'll add that the oil used before when work was done seems to be listed as 'Lube guard' and not the 'Lifeguard' ZF specify.
I'd say shifts in general aren't particularly smooth, a bit jerky really, especially first to second, noticeably worse when cold.
How smooth should the manual mode be when up to temperature and going down the gears? Say 40mph then 4>3>2?
I've only noticed this in the first few minutes of driving from cold and it quickly disappears. When leaving for work it's not long before I hit an NSL section so always see it. When keeping a constant speed, say cruise set a 60, I noticed the revs would hunt from around 2000-2200rpm. Within 30 secs or so I'm turning on to dual carriageway, get up to speed again and the revs stay constant.
On my initial acceleration when hitting the first section of NSL, the car occasionally doesn't want to shift up into the last 2 gears and I do it manually. As above, I'm then shortly turning onto the dual carriageway and it shifts just fine.
I'd say the car can sound a bit whiney, most notable at lower speeds but as I don't have another to compare it to I'm not sure if this is typical.
Torque converter issue? The gearbox itself had a decent amount of work done to it (e65Ross's old car) less than 30k miles ago and the gearbox itself was said to be in fine condition then.
Edit 15/2/18-
I'll add that the oil used before when work was done seems to be listed as 'Lube guard' and not the 'Lifeguard' ZF specify.
I'd say shifts in general aren't particularly smooth, a bit jerky really, especially first to second, noticeably worse when cold.
How smooth should the manual mode be when up to temperature and going down the gears? Say 40mph then 4>3>2?
Edited by Patrick Bateman on Thursday 15th February 18:27
Even though the oil has done less than 30k miles?
Here's a couple of replies to my thread on a BMW forum-
the gearbox has maps to control warm up where it'll allow the box to effectively 'slip' to warm the fluid up. If it's only doing it for the first couple of minutes when it's cold don't worry about it. Mine does this too and as soon as it's been driven for a few minutes, it'll start to lock the torque converter earlier as the heat gets into the fluid. In that 2 minutes when I first start mine the smallest input on the throttle will cause the revs to rise a touch.
I don't think it's too serious, as Mashed Potatoes says the gearbox runs a different program when its oil temperature is below a threshold, 30C I think. That prevents the torque converter from locking up and holds lower gears. The revs hunting is the torque converter failing to lock up fast enough. Probably due to some wear together with cold viscous oil. It might be the case that an alternative to Lifeguard 6 ZF oil has been used and isn't quite as good, or it might be needing an oil change.
I'd read about the warm-up map the gearbox uses when cold but I didn't think this would stop shifting into the higher gears. It'll sit in 4th at about 3000rpm rather than change up.
Here's a couple of replies to my thread on a BMW forum-
the gearbox has maps to control warm up where it'll allow the box to effectively 'slip' to warm the fluid up. If it's only doing it for the first couple of minutes when it's cold don't worry about it. Mine does this too and as soon as it's been driven for a few minutes, it'll start to lock the torque converter earlier as the heat gets into the fluid. In that 2 minutes when I first start mine the smallest input on the throttle will cause the revs to rise a touch.
I don't think it's too serious, as Mashed Potatoes says the gearbox runs a different program when its oil temperature is below a threshold, 30C I think. That prevents the torque converter from locking up and holds lower gears. The revs hunting is the torque converter failing to lock up fast enough. Probably due to some wear together with cold viscous oil. It might be the case that an alternative to Lifeguard 6 ZF oil has been used and isn't quite as good, or it might be needing an oil change.
I'd read about the warm-up map the gearbox uses when cold but I didn't think this would stop shifting into the higher gears. It'll sit in 4th at about 3000rpm rather than change up.
I have a thread going here too- http://forum.bmw5.co.uk/topic/131362-zf-6-speed-tr...
What does anyone make of the post here-
I see what they did, they bodged up a shagged gearbox, lubeguard isn't a typo its a bodgeit and scarper oil. Your box is shagged no doubt, probably going to cost £2500 to put it right if you are lucky.
Zip kit and Lubeguard, they may as well have shoved sawdust in it!
From nothing to worry about to someone thinking the box is shagged, not sure what to think.
What does anyone make of the post here-
I see what they did, they bodged up a shagged gearbox, lubeguard isn't a typo its a bodgeit and scarper oil. Your box is shagged no doubt, probably going to cost £2500 to put it right if you are lucky.
Zip kit and Lubeguard, they may as well have shoved sawdust in it!
From nothing to worry about to someone thinking the box is shagged, not sure what to think.
Edited by Patrick Bateman on Thursday 15th February 18:16
Well I have my 7 back this afternoon, (yaay! 
) and it does (always did) the warm-up slip as mentioned in your quote. Going down the main road 1 mile from cold @ 30mph it’ll cycle between about 1200 and 1500 rpm for a few minutes before being constant.
I am about to take it out for a run, so will have a look on the other side of it to see if I can see anything... Must admit, I rarely drive in manual mode so will have to have a “play”.
) and it does (always did) the warm-up slip as mentioned in your quote. Going down the main road 1 mile from cold @ 30mph it’ll cycle between about 1200 and 1500 rpm for a few minutes before being constant.I am about to take it out for a run, so will have a look on the other side of it to see if I can see anything... Must admit, I rarely drive in manual mode so will have to have a “play”.
Prinny said:
Well I have my 7 back this afternoon, (yaay! ) and it does (always did) the warm-up slip as mentioned in your quote. Going down the main road 1 mile from cold @ 30mph it’ll cycle between about 1200 and 1500 rpm for a few minutes before being constant.
I am about to take it out for a run, so will have a look on the other side of it to see if I can see anything... Must admit, I rarely drive in manual mode so will have to have a “play”.
If you could drop down the gears in manual mode as I describe then that would be grand. ) and it does (always did) the warm-up slip as mentioned in your quote. Going down the main road 1 mile from cold @ 30mph it’ll cycle between about 1200 and 1500 rpm for a few minutes before being constant.I am about to take it out for a run, so will have a look on the other side of it to see if I can see anything... Must admit, I rarely drive in manual mode so will have to have a “play”.
So... three things of note.
Hope that helps - if you want me to try some other things, I’m happy to.
Rob.
- From cold & then crusing to m-way , the 1 mile to m-way showed normal 120-1500 fluctuation as before @ 30mph.
- when then accelerating (relativley gently - still got the rpm limiter at 4.5k - call it 1/3 throttle) upto *cough* around 100 - no issues, box changing at 3k rpm or so, dropping into 5th at 65ish, 6th at 80ish. Slowing down for lights (the A627M is just a spur), no noticeable noises or anything from the box - come to a halt.
- use manual mode to set off, change from M1 to M2 at approx. 4k revs. There’s a bit of driveline shunt - still smooth, but you can’t call it an imperceptible change! As far as I know though, these boxes in the 7’s are not ever using 1st unless manually requested - it certainly doesn’t ever drop into 1 for me unless specifically requested.
Hope that helps - if you want me to try some other things, I’m happy to.
Rob.
Prinny said:
So... three things of note.
Hope that helps - if you want me to try some other things, I’m happy to.
Rob.
How many miles has the car done and has the gearbox ever had any work done?- From cold & then crusing to m-way , the 1 mile to m-way showed normal 120-1500 fluctuation as before @ 30mph.
- when then accelerating (relativley gently - still got the rpm limiter at 4.5k - call it 1/3 throttle) upto *cough* around 100 - no issues, box changing at 3k rpm or so, dropping into 5th at 65ish, 6th at 80ish. Slowing down for lights (the A627M is just a spur), no noticeable noises or anything from the box - come to a halt.
- use manual mode to set off, change from M1 to M2 at approx. 4k revs. There’s a bit of driveline shunt - still smooth, but you can’t call it an imperceptible change! As far as I know though, these boxes in the 7’s are not ever using 1st unless manually requested - it certainly doesn’t ever drop into 1 for me unless specifically requested.
Hope that helps - if you want me to try some other things, I’m happy to.
Rob.
Mine sounds a bit whiny at low speed to my ears but without another to directly compare I'm not sure if it's typical.
That fluctuation sounds more severe than mine. 100-200rpm tops for me. I'd have thought with the warm-up map that the revs would sit higher but not sure why they would hunt like this.
My car goes into 1st itself all the time, it's irritating as it pulls away fine in 2nd and is smoother as 1st>2nd isn't great.
I suppose this could come down to what someone thinks of as smooth but there's certainly no way I'd describe mine as that when at a steady 40 and going from 4th through to 2nd.
Patrick Bateman said:
How many miles has the car done and has the gearbox ever had any work done?
Mine sounds a bit whiny at low speed to my ears but without another to directly compare I'm not sure if it's typical.
That fluctuation sounds more severe than mine. 100-200rpm tops for me. I'd have thought with the warm-up map that the revs would sit higher but not sure why they would hunt like this.
My car goes into 1st itself all the time, it's irritating as it pulls away fine in 2nd and is smoother as 1st>2nd isn't great.
I suppose this could come down to what someone thinks of as smooth but there's certainly no way I'd describe mine as that when at a steady 40 and going from 4th through to 2nd.
Car’s now at 82k, bought December ‘16 at 78k and did a gearbox filter & fluid at time of purchase.Mine sounds a bit whiny at low speed to my ears but without another to directly compare I'm not sure if it's typical.
That fluctuation sounds more severe than mine. 100-200rpm tops for me. I'd have thought with the warm-up map that the revs would sit higher but not sure why they would hunt like this.
My car goes into 1st itself all the time, it's irritating as it pulls away fine in 2nd and is smoother as 1st>2nd isn't great.
I suppose this could come down to what someone thinks of as smooth but there's certainly no way I'd describe mine as that when at a steady 40 and going from 4th through to 2nd.
The actual warm-up isn’t noticeable by way of driving, it’s only looking at the rev. counter needle that you even know it’s happening.
I suspect - based on what you say, the logic is different for the v8 vs. v12 - mine really doesn’t use 1st at all - I’ll get some video up (I haz dashcam) for you tomorrow, hopefully it’ll show my perceptions of “smooth”.
Prinny said:
Car’s now at 82k, bought December ‘16 at 78k and did a gearbox filter & fluid at time of purchase.
The actual warm-up isn’t noticeable by way of driving, it’s only looking at the rev. counter needle that you even know it’s happening.
I suspect - based on what you say, the logic is different for the v8 vs. v12 - mine really doesn’t use 1st at all - I’ll get some video up (I haz dashcam) for you tomorrow, hopefully it’ll show my perceptions of “smooth”.
Yes I agree, it's only through looking at the rev counter I'm aware of anything.The actual warm-up isn’t noticeable by way of driving, it’s only looking at the rev. counter needle that you even know it’s happening.
I suspect - based on what you say, the logic is different for the v8 vs. v12 - mine really doesn’t use 1st at all - I’ll get some video up (I haz dashcam) for you tomorrow, hopefully it’ll show my perceptions of “smooth”.
Cheers.
Firstly, have an oil a filter change of the 'box. Use the proper ZF oil, and it must be done using a diagnostics tool to measure the temperature - the level must be set in a particular temperature range - if not, the oil level is all wrong and shifts are not very nice. Also, the computer adaptations can be reset to factory default - auto boxes use "fuzzy logic" to "learn" the driving style, and will readapt over time to suit the driver.
When my wife had her transmission serviced, we noted immediately that the shifting was far smoother.
I found an article some months ago which stated that the lock-up clutch in the torque converter does not engage when the fluid temperautre is below 35 deg.C (iirc - certainly between 30 and 35).
When my wife had her transmission serviced, we noted immediately that the shifting was far smoother.
I found an article some months ago which stated that the lock-up clutch in the torque converter does not engage when the fluid temperautre is below 35 deg.C (iirc - certainly between 30 and 35).
When you say they did a decent amount of work to the box, you need to go into further detail because what they did was a refurb of the valve body and new fluid.
They didn't touch the torque convertor.
My guess would be that the TC is on the way out.
Mackie's in Glasgow can rebuild. I don't know whether it's cost effective to only swap out the TC without for example replacing the clutch packs with new, or any other ZF upgrades (I believe that's the 6 speed).
Therefore reckon on about £2 grand's worth of work if that's the case
They didn't touch the torque convertor.
My guess would be that the TC is on the way out.
Mackie's in Glasgow can rebuild. I don't know whether it's cost effective to only swap out the TC without for example replacing the clutch packs with new, or any other ZF upgrades (I believe that's the 6 speed).
Therefore reckon on about £2 grand's worth of work if that's the case
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