BMW and M Power Owners
- Thread starter panthro
- Start date
Also. I have no idea why because I can't see how it's related..
Basically I had to swap a runflat on the rear right . Which was a 255/40 R18 pirelli with another runflat pirelli, same size same sort of spec this afternoon . Drives ok sound wise..no vibrations. But since taking it the local tyre place it seems to be weird on zf auto gear shifting . It's holding on to rpms up to 2800 - 3000 rpm before changing . When usally it would be around 2000 rpm .
Is there anything linked in the ECU and the tyres / speed /rpm that adjusts.? Why would this happen ?. I could understand traction etc but not anything to do with transmission
Iv tried to put it in manual.mode and change back . Just got back from a drive going to turn off and go for another quick tested
Edit: yes it does seem to be driving abit strange. In sport mode it's holding on to the rpms during gear shifting a lot longer . IE if I put my foot down in sport mode it holds on to some of the gears to about nearly 3000rpm ? Seems abit high?
Basically I had to swap a runflat on the rear right . Which was a 255/40 R18 pirelli with another runflat pirelli, same size same sort of spec this afternoon . Drives ok sound wise..no vibrations. But since taking it the local tyre place it seems to be weird on zf auto gear shifting . It's holding on to rpms up to 2800 - 3000 rpm before changing . When usally it would be around 2000 rpm .
Is there anything linked in the ECU and the tyres / speed /rpm that adjusts.? Why would this happen ?. I could understand traction etc but not anything to do with transmission
Iv tried to put it in manual.mode and change back . Just got back from a drive going to turn off and go for another quick tested
Edit: yes it does seem to be driving abit strange. In sport mode it's holding on to the rpms during gear shifting a lot longer . IE if I put my foot down in sport mode it holds on to some of the gears to about nearly 3000rpm ? Seems abit high?
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Soldato
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- 14 Apr 2014
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No it's not an x drive just standard rear wheel drive.
Tread depth is about 5.2mm on rear left and maybe about 4.9- 5 on rear right ? At a guess ? As I dont have a gauge.. psi is slightly lower on rear right than other 4 corners as the garage didn't spec it to what I had in other wheels
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"Foot down" in sport should be getting near the limiter each shift really
I have had a look on Google which suggests
BMW 420d (2018) automatic transmission holding gears to 2500-3000 RPM after a tire change is unusual. It's more likely a coincidence that the issue appeared after the tire change, as the two are not directly related. The problem is likely due to an issue with the car's adaptive transmission learning process, a low transmission fluid level, or a faulty solenoid.
Here's a more detailed explanation:
1. Adaptive Transmission Learning:
BMW's automatic transmissions adapt to driving styles and conditions. After a tire change, the car's systems may need to recalibrate, potentially causing unusual shifting patterns.
To address this, you can try resetting the transmission's adaptive settings. A BMW diagnostic website advises to turn the ignition to the "on" position (without starting the engine), fully depress the accelerator pedal, and hold it for 25-30 seconds. This should reset the transmission's learned parameters.
2. Low Transmission Fluid:
Low transmission fluid can cause erratic shifting, including holding gears longer than usual.
If you suspect this, have the transmission fluid level checked by a qualified mechanic.
3. Faulty Solenoid:
A faulty shift solenoid can also cause delayed or erratic shifting, including holding gears for too long.
This is a more complex issue and would require inspection by a mechanic.
4. Other Potential Issues:
While less likely, other issues like a vacuum leak (affecting engine performance and potentially transmission behavior) or a failing torque converter (more common in automatic BMWs) could be contributing factors.
In summary: It's recommended to first try resetting the transmission's adaptive learning. If the problem persists, have the transmission fluid level checked and consider a professional diagnosis to identify and address any potential solenoid or other issues.
Adaptive transmission learning ?
It defenatly holds on to them way longer than before I'm sure of it. It was very snappy before and usually around 2000 to 2200 rpm maybe I can't remember. I'll have a drive over next few days. I'll also top up the air in the rear right so all 4 corners match. I'll have a look at this adaptive transmission learning
BMW 420d (2018) automatic transmission holding gears to 2500-3000 RPM after a tire change is unusual. It's more likely a coincidence that the issue appeared after the tire change, as the two are not directly related. The problem is likely due to an issue with the car's adaptive transmission learning process, a low transmission fluid level, or a faulty solenoid.
Here's a more detailed explanation:
1. Adaptive Transmission Learning:
BMW's automatic transmissions adapt to driving styles and conditions. After a tire change, the car's systems may need to recalibrate, potentially causing unusual shifting patterns.
To address this, you can try resetting the transmission's adaptive settings. A BMW diagnostic website advises to turn the ignition to the "on" position (without starting the engine), fully depress the accelerator pedal, and hold it for 25-30 seconds. This should reset the transmission's learned parameters.
2. Low Transmission Fluid:
Low transmission fluid can cause erratic shifting, including holding gears longer than usual.
If you suspect this, have the transmission fluid level checked by a qualified mechanic.
3. Faulty Solenoid:
A faulty shift solenoid can also cause delayed or erratic shifting, including holding gears for too long.
This is a more complex issue and would require inspection by a mechanic.
4. Other Potential Issues:
While less likely, other issues like a vacuum leak (affecting engine performance and potentially transmission behavior) or a failing torque converter (more common in automatic BMWs) could be contributing factors.
In summary: It's recommended to first try resetting the transmission's adaptive learning. If the problem persists, have the transmission fluid level checked and consider a professional diagnosis to identify and address any potential solenoid or other issues.
Adaptive transmission learning ?
It defenatly holds on to them way longer than before I'm sure of it. It was very snappy before and usually around 2000 to 2200 rpm maybe I can't remember. I'll have a drive over next few days. I'll also top up the air in the rear right so all 4 corners match. I'll have a look at this adaptive transmission learning
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Soldato
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Sounds like you knocked the gearbox in to S mode.
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No I was in sport mode. Sport mode is usually quite snappy on the gear shifting. Now its holding to the rpms more
I'll keep an eye on it over next day or two
Spray paint like acrylic based or plastidip. Any coatings like the Megs stuff will need re-applying.
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Soldato
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- 10 Oct 2006
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- 3,688
Sports mode should be changing higher up the revs over normal drive,on the 6 cylinder diesels in drive it would change approx 2.2k and 3k in sport mode if not going full throttle.
Soldato
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- 18 Oct 2002
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- The land of milk & beans
That's exactly what Sport mode is supposed to do.
I'll do around 10-15k in the car, so need to take that into consideration.
Spray. A brush won't provide a good finish on plastic unless you are highly skilled at brushwork. To spray paint it: You need to remove it, key it down with 800 grit, prime it and then finish with satin black. It may look a slightly different shade to the rest of the trim on the seat but it will at least be black.
Or, before doing that, try what Bear suggested and use an open flame. Just be careful not to melt the plastic. If that fails to restore the finish, then paint it.
I assume you're concerned about depreciation? Definitely go for high mileage on that basis - the majority of the depreciation is done already. Taking a 35k car to 50k in a year is going to be a sting, but taking a 100k car to 115k isn't really going to dent it all that much. People that worry about 100k+ Porsches don't know how to hold screwdrivers. Actually, most Porsche drivers don't generally, but that's another topic entirely.I'll do around 10-15k in the car, so need to take that into consideration.
Nonetheless, it's important to remember that a car is a liability and is pretty much a guaranteed way to part with at least some of your cash. If I recall in recent weeks; weren't you looking at a G20/G30, then an M3, now 996/997 Turbo? These are all drastically different cars - what are you truly looking for?
Taken it out of sport?