Is it the transmission ??

[Patrick-Irish]

Before I go to an auto gearbox specialist and incur what it likely to be a high cost, I'd like to bounce it off this forum first to see what you think.

I've got a 2001 X5 4.4i. 108k miles on the clock.

There is a sporadic hesitation in the car pretty much at all speeds. By hesitation I mean as you drive along you can feel half second dips in power. At slower speeds it can occasionally be quiet pronounced and happens not in any steady kind of pattern but definately every 10 seconds or less it can be felt, just for a half second. If I keep my eye on the rev counter it can be seen to fall back slightly as well. At steady motorway speeds it can be felt too, though not quiet as pronounced.

The gears can be slow to engage, when shifting from park to drive or into reverse. It can take maybe a second to engage the gear. Very occasionally the car jerks slightly when reverse is selected.

I am fairly sure the box has leaked some of the fluid out of it too. There are quiet a few drips on the drive.

Sounds like a transmission issue straight away. But the thing putting doubt in my mind is the rev counter dipping. Why would the revs dip if it was a transmission problem ? I would have thought this might indicate some sort of engine problem.

Another thing. The weather suddenly went really cold this morning, and I didn't really feel the issue in the car when going to work. So now I'm thinking air intake ........ it's well known performance can change with changing air temperature and density. Maybe the engine was getting more air this morning and was overcoming the problem. So again, that points away from the transmission and more towards the engine, air intake or air mass meter issue for example.

So what do you think ? Anyone have this issue before and found the solution ? Any comments and advice welcome.

Thanks.

[Jordo]

This is my first x5 and I have exactly the same thing. There is many threads talking about this issue. Search it and you'll see your not alone.

[statdoc]

It wasn't the transmission in my case. Read HERE for my story.

[Patrick-Irish]

Folks,

I can't believe the number of threads being posted relating to the tranny. I didn't realise until after I posted mine and then started looking around the forum. And a lot of them pretty similar.

I installed a new battery on Saturday. This was not motivated in any way by my tranny problem, but I had left the interior light on a month or so ago and the battery went flat. I had to jump start it and while since then it seemed to be keeping its charge ok, I was unsure how old it was and wanted to change it for comfort.

The one I took out was some sort of brand x job. Definately not a BMW original and I suspect may be a cheqp option someone took in the past before I owned the car. The one I put in was a very expensive one, top of the range from a very well known and trusted brand. It also has much more juice .... 100Ah versus the 85Ah thing I took out. For comparison the one in my wifes Toyota puts out 60Ah, so it's a formidable battery.

Anyway, oddly enough, I am not getting that funny tranny judder any more. And the car seems more willing to get up and go when I push the accelerator peddle. I was kinda stunned to be honest ..... I hadn't anticipated this effect from changing the battery. I am still keeping the situation very much under observation, but there is a definate change in how the car is behaving since the new battery went in.

So, does it make any sense to anyone that a weak battery might cause such a drivability problem ?

I should mention that I purposefully took the old battery out and didn't install the new one for at least 30 minutes. I figured this might reset some systems in the car ..... though I couldn't tell you what systems. I gave it a go anyway.

So I'll be back with progress and whatever observations I notice.

Finally, my daughter pushed up her first tooth today. Hurray !!!

[Jordo]

Well congrats on the first tooth! Big step!

Well the battery that I have has some numbers on it but it is the cca, (cold cranking amps). It doesn't talk about the numbers you talked about. But as you can see it's no BMW issued battery.

This is what I have.



Any help?

[Patrick-Irish]

I did a little research there and discovered that standards differ in the US v's Europe with regard to how they quote battery figures. Here is a link to the one I installed. Unfortunately I have no idea how to reconcile the figures for this battery to yours.

Bosch Automotive Parts - Batteries - Cars: S6