Transmission Reliability

[ncsucarjock]

Well, you hear lots of rumors about the transmissions going bad. But, after over a year on this forum, I've only seen about 3 transmission died posts, and in one of those cases it was not the transmission.

Do they die? Sure. Frequently? No. Especially not if you change the fluid every 50k. And I don't think I've heard of one failing prior to 100k miles.

Manual will always be the most reliable, but they're also the rarest, and only come with an anemic (in my opinion, in the x) six-cylinder. Get a V8, change the fluid, drive it till it dies...

[willgabriel]

Originally Posted by ncsucarjock

Well, you hear lots of rumors about the transmissions going bad. But, after over a year on this forum, I've only seen about 3 transmission died posts, and in one of those cases it was not the transmission.

Do they die? Sure. Frequently? No. Especially not if you change the fluid every 50k. And I don't think I've heard of one failing prior to 100k miles.

Manual will always be the most reliable, but they're also the rarest, and only come with an anemic (in my opinion, in the x) six-cylinder. Get a V8, change the fluid, drive it till it dies...

And this is where I am confused. I have seen just as many reliable experts claim you should NEVER change the transmission fluid, as say you should at 50k and 100k, etc ... so, which is it, and why? IMO, I don't think anybody is an expert on these transmissions; it really is 6 of one and 1/2 dozen of the other when it comes to "how to guarantee long transmission life" simply because the unreliability problems associated with the transmission don't seem to have been solved to a point of a consensus answer. Frankly, if Toyota can step up to the plate and recall so many 5 year old and newer vehicles due to throttle issues, BMW should be able to do the same for the X5 transmission issues ESPECIALLY since they were originally tagged as NOT needing fluid changes for the LIFETIME of the vehicle (and if the "lifetime" for a transmission on a $60k luxury vehicle is not more than 150k miles, that's pathetic).

[Quicksilver]

There have been so many transmission fights pro and con
about changing the fluid that no one will ever agree.
Just do a search and see what I mean.........

Originally Posted by willgabriel

And this is where I am confused. I have seen just as many reliable experts claim you should NEVER change the transmission fluid, as say you should at 50k and 100k, etc ... so, which is it, and why? IMO, I don't think anybody is an expert on these transmissions; it really is 6 of one and 1/2 dozen of the other when it comes to "how to guarantee long transmission life" simply because the unreliability problems associated with the transmission don't seem to have been solved to a point of a consensus answer. Frankly, if Toyota can step up to the plate and recall so many 5 year old and newer vehicles due to throttle issues, BMW should be able to do the same for the X5 transmission issues ESPECIALLY since they were originally tagged as NOT needing fluid changes for the LIFETIME of the vehicle (and if the "lifetime" for a transmission on a $60k luxury vehicle is not more than 150k miles, that's pathetic).

[Supernatural]

Originally Posted by ncsucarjock

Manual will always be the most reliable, but they're also the rarest, and only come with an anemic (in my opinion, in the x) six-cylinder.

I disagree with your assumption. While the 3.0 is not the biggest powerhouse in the Bmw fray, it is no stone. Whoopie a 4.4 auto won by a car length. Furthermore I would like to see a run with a chipped 3.0 or a SC'd one.

YouTube - BMW X5 4.4 (automatic transmission) vs BMW X5 3.0 (manual transmission)

[m5james]

Originally Posted by Supernatural

I disagree with your assumption. While the 3.0 is not the biggest powerhouse in the Bmw fray, it is no stone. Whoopie a 4.4 auto won by a car length. Furthermore I would like to see a run with a chipped 3.0 or a SC'd one.

YouTube - BMW X5 4.4 (automatic transmission) vs BMW X5 3.0 (manual transmission)

That looks like at least 3 cars lengths to me. Besides doing some 0-60 or whatever run like that, it's also the immediate power when floored. I've been in enemic vehicle that we're completely terrible at trying to pass with. There are times when the 4.4 hasn't felt like it was enough at times, so I can't imagine what the 3.0 would feel like. Gotta pay to play I guess. Chipped still wouldn't make a 3.0 as fast as a 4.4, and the S/C is the same price for a 3.0 or 4.4, so either can be modified to get a substantial gain. Don't get me wrong though, when I first was looking at X5's (pre 740iL) I was looking at a 3.0/5 spd to treat just like a 330ci...headers, large turbo, etc. Only problem was that there was NO aftermarket support for tuning. Nowadays, it's more available, but by no means is it cheap.

[ncsucarjock]

I"m sorry you don't have the V8. One, I can't drive a manual, due to knee issues. 5 speed isn't an issue, so if you want to compare apples to apples, you have to do an automatic 3.0...

And then...lets put 6000# behind it, and head for the mountains. I think you'll find the 3.0 becomes very labored with that, manual or automatic. As I tow between 3000-7000 miles a year with that load... That's a pretty crucial measurement for me.

Back to the original posters question about changing fluid, this is all I can say. I've been through mechanics school...

No fluid lasts forever. They *all* break down. We know that transmissions are one of the most expensive items in a car, and yet, we dont' want to perform basic fluid changes because manufacturers have trained the public that "maintenance" is bad, and should be avoided - a perfect car would run perfectly forever, with zero maintenance. After coming back down to earth from the space dream, let's realize that all fluids - cooling, oil, transmission, differential, transfer case, power steering fluid, *all* degrade. There are recommended intervals for most of these. In my opinion (and this is *just* my opinion) regular fluid changes of all fluids are crucial to longevity. This does not mean I advocate 3000 mile oil changes, but I do recommend using some common sense.

I use this rule when it comes to automatic transmissions:
1) fluid breaks down, more in heavy use situations. Changing every 30,000 - 50,000 miles with a good quality compatible synthetic is a must do, regardless of what any manufacturer says.

2) fluid "flushes" are BAD juju. This is when they use a machine to pump your old fluid out, and new fluid in. The power for doing this is provided by the pump on the machine. I've heard of many instances where this procedure has damaged transmissions, probably due to excessive pump pressure.

3) If you disconnect the transmission line at the cooler, and start the engine, using the transmission pump to pump out fluid, this is an acceptable means of "pumping" the fluid out. This will allow a more complete fluid change, but it takes a lot longer, because you need to stop every 1/2 gallon (two quarts) and refill the transmission pan. On the BMW X5, at least on my V8, this is not easy to do. I prefer to just drop the entire pan, remove the filter, check for any excessive metal or sediment (and at 50k, I found none), replace the fluid, and call it good.

I will change again at 100k miles, and probably 150 and 200. For the record, for those that have changed fluid every 30-50k religiously, I've not heard of a transmission dying. If there's is one that has failed, I'd be pretty surprised, and willing to blame it on an improperly made part or assembly.

By and large though, transmissions are pretty simple devices. Sure, they have more gears, and electronic controls, but the basics have not changed since the first automatics came out more than 50 years ago. And regular fluid changes were required for decades before this whole "non-maintenance" scheme started appearing in the 90's.

For the record, I also change my engine oil every 10k miles, and the differential fluid every 50k, and the transfer case fluid every 50k as well. All of these are synthetic fluids, if they were conventional, I'd change more frequently, but I don't like conventional fluids, and dont' run them in any of my vehicles.

Also worth noting, changing your brake fluid every 2-3 years is part of required maintenance, and so is changing your antifreeze about the same time.

Do all this, along with plugs, filters, keeping it clean, attending to any leaks, and you'll be shocked how long a well maintained vehicle will run.

[m5james]

Originally Posted by cheappc

I read about transmissions going bad on the x's before I bought mine... so tell me people lets get honest here, which transmissions go bad?
1. The 5 speed auto?
2. The 6 speed auto?
3. The 5 speed manual?

These are just generalizations, but...

I'd say the 5spd can be more reliable if serviced. Debates in regards to the pros and cons can be found all day long, but plain ol' common sense tell me that NO fluid is ever lifetime.

The 6spd's are newer and apparently have been breaking down just as frequently as the 5spd's, but the difference is...most of those 5spd's are over 100k, while the 6spd's are newer and should still be in a lower mileage range.

The manual isn't perfect either, I've read threads over the years of people having synchro issues, popping out of gear, etc. For some reason my M5 uses ATF in it's 5spd manual, and just like the fluid servicing debate, you will find just as many people who've have good or bad luck w/ fluid changes in those transmission as well.

I still believe that going super long intervals on stock fluids just isn't a good idea, but that's just me. 50k fluid changes and nothing has failed yet, so I'm gonna keep doing what I've always done. Just changed the fluid in my 90 Chevy winter beater a few months back, all 270k on the odo and still shifts perfectly fine, w/ and w/o the trailer.

I'm sure someone can find information contrary to this, but pay attention to the paragraph in regards to the Automatic Transmission Rebuilders Association opinions, who will know more than any of us armchair mechanics will ever know. How often should the automatic transmission fluid... — Yahoo! Autos

[willgabriel]

Originally Posted by ncsucarjock

I"m sorry you don't have the V8. One, I can't drive a manual, due to knee issues. 5 speed isn't an issue, so if you want to compare apples to apples, you have to do an automatic 3.0...

And then...lets put 6000# behind it, and head for the mountains. I think you'll find the 3.0 becomes very labored with that, manual or automatic. As I tow between 3000-7000 miles a year with that load... That's a pretty crucial measurement for me.

Back to the original posters question about changing fluid, this is all I can say. I've been through mechanics school...

No fluid lasts forever. They *all* break down. We know that transmissions are one of the most expensive items in a car, and yet, we dont' want to perform basic fluid changes because manufacturers have trained the public that "maintenance" is bad, and should be avoided - a perfect car would run perfectly forever, with zero maintenance. After coming back down to earth from the space dream, let's realize that all fluids - cooling, oil, transmission, differential, transfer case, power steering fluid, *all* degrade. There are recommended intervals for most of these. In my opinion (and this is *just* my opinion) regular fluid changes of all fluids are crucial to longevity. This does not mean I advocate 3000 mile oil changes, but I do recommend using some common sense.

I use this rule when it comes to automatic transmissions:
1) fluid breaks down, more in heavy use situations. Changing every 30,000 - 50,000 miles with a good quality compatible synthetic is a must do, regardless of what any manufacturer says.

2) fluid "flushes" are BAD juju. This is when they use a machine to pump your old fluid out, and new fluid in. The power for doing this is provided by the pump on the machine. I've heard of many instances where this procedure has damaged transmissions, probably due to excessive pump pressure.

3) If you disconnect the transmission line at the cooler, and start the engine, using the transmission pump to pump out fluid, this is an acceptable means of "pumping" the fluid out. This will allow a more complete fluid change, but it takes a lot longer, because you need to stop every 1/2 gallon (two quarts) and refill the transmission pan. On the BMW X5, at least on my V8, this is not easy to do. I prefer to just drop the entire pan, remove the filter, check for any excessive metal or sediment (and at 50k, I found none), replace the fluid, and call it good.

I will change again at 100k miles, and probably 150 and 200. For the record, for those that have changed fluid every 30-50k religiously, I've not heard of a transmission dying. If there's is one that has failed, I'd be pretty surprised, and willing to blame it on an improperly made part or assembly.

By and large though, transmissions are pretty simple devices. Sure, they have more gears, and electronic controls, but the basics have not changed since the first automatics came out more than 50 years ago. And regular fluid changes were required for decades before this whole "non-maintenance" scheme started appearing in the 90's.

For the record, I also change my engine oil every 10k miles, and the differential fluid every 50k, and the transfer case fluid every 50k as well. All of these are synthetic fluids, if they were conventional, I'd change more frequently, but I don't like conventional fluids, and dont' run them in any of my vehicles.

Also worth noting, changing your brake fluid every 2-3 years is part of required maintenance, and so is changing your antifreeze about the same time.

Do all this, along with plugs, filters, keeping it clean, attending to any leaks, and you'll be shocked how long a well maintained vehicle will run.

This is a great explanation for why we should change the transmission fluid every 50k miles. Thank you. Additionally, I think it provides further evidence that could (and should) be submitted in a formal complaint against BMW as they have insisted before the newest X5's were produced, that the transmission fluids were "lifetime" fluids. As such, they should bear a great portion of the financial burden incurred for any 2000-2008 BMW X5 transmission that has failed before, say, 150k miles.

[Fraser]

Originally Posted by cheappc

I read about transmissions going bad on the x's before I bought mine... so tell me people lets get honest here, which transmissions go bad?
1. The 5 speed auto?
2. The 6 speed auto?
3. The 5 speed manual?

Don't forget about the six-speed manual!

[Quicksilver]

My suggestion is the same as it was before
"There have been so many transmission fights pro and con
about changing the fluid that no one will ever agree.
Just do a search and see what I mean.........

This discussion has been going on since day one and the failure rate
of transmissions based on the "lifetime" fluids" issue
or change it conclusion has never met a formal complaint
criteria against BMW period.

Originally Posted by willgabriel

This is a great explanation for why we should change the transmission fluid every 50k miles. Thank you. Additionally, I think it provides further evidence that could (and should) be submitted in a formal complaint against BMW as they have insisted before the newest X5's were produced, that the transmission fluids were "lifetime" fluids. As such, they should bear a great portion of the financial burden incurred for any 2000-2008 BMW X5 transmission that has failed before, say, 150k miles.