E36 Switchtronic woes.

Mickl · Post by **Mickl** » Sat Oct 22, 2016 5:23 pm

I am not sure if anyone has experienced this problem?

My 95 e36 swithtronic gearbox seems to have a bit of a mind of its own.
I was using in switchtronic mode the other day and the indicator on the dash was showing the gear changing between 4th and 5th with the dash coming up in between even though I hadn't pressed either button to change. I was in 4th at the time, it also sometimes feels like it has changed up but the indicator shows the same gear. Seems to be when I was coasting, ie no or little throttle input.

I wondered if anyone has experienced anything like this and if it is gearbox related or an electronic problem.
All seems to be normal in auto.

Thanks

Mick

MCB · Post by **MCB** » Tue Oct 25, 2016 2:39 am

Sorry Mick, cant help you with that one. We don't often use it in switch-tronic mode. But the couple of times we have I cant say that I have noticed what you mentioned. The first time I used it however I did notice the dash indicator only went up to 5. In fully auto mode it goes through 6 changes.

Have you had a fluid and filter change recently? We had ours done and I must say it made a big difference in gear changes.

shaziman · Post by **shaziman** » Tue Oct 25, 2016 8:40 am

Sounds like a classic 5HP18 box! Change the oil and filter, possibly twice depending on when it was last changed, and you will probably find this will stop.

Mickl · Post by **Mickl** » Tue Oct 25, 2016 8:08 pm

Thanks guys

Yes filter and fluid changed a few thousand miles ago, I was in Daniel James yesterday and mentioned it to them and they said the same.

I will have to monitor things to see what develops.

Mick

MCB · Post by **MCB** » Tue Oct 25, 2016 10:42 pm

The problem is Mick, that although the fluid in the box gets drained the old fluid still remains in the torque converter. I appreciate it is a rather expensive experiment, but as Shaziman suggested a second fluid change may help.

Please keep us posted on any new developments.

nealpina · Post by **nealpina** » Fri Oct 28, 2016 1:00 am

By the lack of revs there could be an another fault - it can also be the MAF or C02 sensor - canâ€™t remember which one now that can cause the gearbox to have this odd behaviour

Doesnâ€™t sound like a minor bug which I have found with the display. I can trick my display showing either 4 or 5, when I am either in 4 or 5. Switchironic has to be selected and in gear 5, and I then manually move the gear lever down to 2 and move up to either 4 or D and the display will show the other gear for a few seconds until it realises what I done. Not done this trick for about 7 years hence why my memory is a bit rusty with this trick.

nealpina · Post by **nealpina** » Fri Oct 28, 2016 1:01 am

MCB wrote:The first time I used it however I did notice the dash indicator only went up to 5. In fully auto mode it goes through 6 changes.

MCB not sure what you mean? as a B3 3.2 only has 5 forward gears

shaziman · Post by **shaziman** » Fri Oct 28, 2016 1:36 pm

First signs of a 5HP18 failing is 6 changes. It stops in 2nd, then when you pull away suddenly changes into first and then through the sequence, suggesting 6 speeds, when there are only 5 gears.

I found this on my old 325, and this then lead to the 'mind of its' own and a fluid changed helps, but damage was done that didn't really seem to fix itself. Spoke to several specialists, and they all said to change the box, not so easy on an Alpina!

Touch wood, my box is perfect in the B3, but had several bad experiences in the 325.

Post by **Charles** » Fri Oct 28, 2016 2:32 pm

Have a chat with Bill at Stephens Engineering, who refurbished my 5HP19 recently (and beautifully too):

Highly experienced and knowledgeable and was able to diagnose over the phone that the F-drum in my box was cracked.

Worth a discussion in the first instance

MCB · Post by **MCB** » Fri Oct 28, 2016 2:53 pm

nealpina wrote:
MCB wrote:The first time I used it however I did notice the dash indicator only went up to 5. In fully auto mode it goes through 6 changes.
MCB not sure what you mean? as a B3 3.2 only has 5 forward gears

Well when in auto mode I am sure that I can count 6 up changes. Of course that includes 1st that you pull away with. So 5 changes after pulling away from standstill. Where in switch-tronic mode you can only change up to 5. I just assumed that 6th was a type of overdrive that would not be required in sport/switch-tronic mode. Please don't tell me I am wrong and there is something wrong with the box

I determined this by pulling away gently and smoothly until reaching top gear. I have never questioned this before, because the gearbox has appeared to perform perfectly during the 5,000 miles of our ownership.

EDIT: I have not had cause to check it since the fluid change last year, but next time I take it out I will carry out the same test again and see what happens.

Post by **Charles** » Fri Oct 28, 2016 5:27 pm

MCB wrote:
nealpina wrote:
MCB wrote:The first time I used it however I did notice the dash indicator only went up to 5. In fully auto mode it goes through 6 changes.
MCB not sure what you mean? as a B3 3.2 only has 5 forward gears
Well when in auto mode I am sure that I can count 6 up changes. Of course that includes 1st that you pull away with. So 5 changes after pulling away from standstill. Where in switch-tronic mode you can only change up to 5. I just assumed that 6th was a type of overdrive that would not be required in sport/switch-tronic mode. Please don't tell me I am wrong and there is something wrong with the box I determined this by pulling away gently and smoothly until reaching top gear. I have never questioned this before, because the gearbox has appeared to perform perfectly during the 5,000 miles of our ownership.

EDIT: I have not had cause to check it since the fluid change last year, but next time I take it out I will carry out the same test again and see what happens.

Perhaps the phantom 6th change is the lock-up clutch engaging once steady state has been reached?

Mickl · Post by **Mickl** » Fri Oct 28, 2016 6:47 pm

Charles wrote:Have a chat with Bill at Stephens Engineering, who refurbished my 5HP19 recently (and beautifully too):

Highly experienced and knowledgeable and was able to diagnose over the phone that the F-drum in my box was cracked.

Worth a discussion in the first instance

Thanks Charles

Might be worth a call.

Mick

MCB · Post by **MCB** » Sat Oct 29, 2016 12:00 am

Charles wrote:
MCB wrote:
nealpina wrote:
MCB wrote:The first time I used it however I did notice the dash indicator only went up to 5. In fully auto mode it goes through 6 changes.
MCB not sure what you mean? as a B3 3.2 only has 5 forward gears
Well when in auto mode I am sure that I can count 6 up changes. Of course that includes 1st that you pull away with. So 5 changes after pulling away from standstill. Where in switch-tronic mode you can only change up to 5. I just assumed that 6th was a type of overdrive that would not be required in sport/switch-tronic mode. Please don't tell me I am wrong and there is something wrong with the box I determined this by pulling away gently and smoothly until reaching top gear. I have never questioned this before, because the gearbox has appeared to perform perfectly during the 5,000 miles of our ownership.

EDIT: I have not had cause to check it since the fluid change last year, but next time I take it out I will carry out the same test again and see what happens.
Perhaps the phantom 6th change is the lock-up clutch engaging once steady state has been reached?

That could be a possibility Charles. I will monitor it more closely next time we have her out. I will probably use the rev counter this time to see if there is a drop, if and when the "phantom 6th" is felt.