Let's talk Transmission Maintenance...

[JCL]

Originally Posted by diesaroo

I do agree with you however that there will always be cases of transmission failure that are the result of a bad internal parts failing unrelated to fluid condition, although I would tend to believe that they would show up earlier in the vehicles service life than later on and would be likely during the warranty period.

See my post #29 in this thread. I provided an article on paradigms of maintenance, which discusses whether failures in complex systems are more likely to occur with time, or not. My point is that the transmission failures most will see are not in fact wear out, but are due to random mechanical and electrical failures.

Originally Posted by diesaroo

I personally just can't seem to enjoy car ownership if I adopt a defeatist attitude and allow the car to degrade and wear out by following a bare bones-I-will-if-I-have-to maintenance schedule. I am not trying to offend you, but whatever happened to taking pride in your machine?

I am not offended, but you don't know me, and you are prescribing opinions to me that are incorrect. I am a car nut. I like working on my own vehicles, for the pleasure of doing the work as much as for the outcomes. I am not at all defeatist. There is nothing bare-bones about my personal maintenance strategies. While I take pride in my vehicles, I just don't see the logic in taking pride in having changed a fluid that didn't need changing, thereby introducing potential contamination to a sealed system, and raising the chances of infant mortality post-change. Maintenance is a science, not a black art, or act of faith, IMO. Recommend again that you look at the attachment in my post #29.


Jeff

[diesaroo]

Originally Posted by JCL

See my post #29 in this thread. I provided an article on paradigms of maintenance, which discusses whether failures in complex systems are more likely to occur with time, or not. My point is that the transmission failures most will see are not in fact wear out, but are due to random mechanical and electrical failures.




I am not offended, but you don't know me, and you are prescribing opinions to me that are incorrect. I am a car nut. I like working on my own vehicles, for the pleasure of doing the work as much as for the outcomes. I am not at all defeatist. There is nothing bare-bones about my personal maintenance strategies. While I take pride in my vehicles, I just don't see the logic in taking pride in having changed a fluid that didn't need changing, thereby introducing potential contamination to a sealed system, and raising the chances of infant mortality post-change. Maintenance is a science, not a black art, or act of faith, IMO. Recommend again that you look at the attachment in my post #29.


Jeff

Ok Jeff, I apologize if my comment was a little "below the belt." And I agree that you are a certified car nut, what seems to me from your signature is that you generally prefer manual trannies. Nothing wrong with that as I would too if the wife could drive them.

I agree that there is always a chance of failure whenever any maintenance is performed whether that be engine oil and filter change or other fluids, but as long as the person performing the service knows what they're doing and has experience, the right tools and supplies, the risk is extremely low.

Just out of curiosity, what fluids do you feel on a vehicle should be changed and at what intervals? And what data do you have to substantiate those maintenance schedules?

[JCL]

Originally Posted by diesaroo

Ok Jeff, I apologize if my comment was a little "below the belt." And I agree that you are a certified car nut, what seems to me from your signature is that you generally prefer manual trannies. Nothing wrong with that as I would too if the wife could drive them.

I agree that there is always a chance of failure whenever any maintenance is performed whether that be engine oil and filter change or other fluids, but as long as the person performing the service knows what they're doing and has experience, the right tools and supplies, the risk is extremely low.

Just out of curiosity, what fluids do you feel on a vehicle should be changed and at what intervals? And what data do you have to substantiate those maintenance schedules?

My wife insists on a manual transmission. Both our daughters drive manuals. I have owned lots of automatics (as many vehicles don't give you a choice).

While there is a chance of failure whenever maintenance is done, I don't equate an oil change with a transmission fluid change. If the oil change is done correctly (procedure, fluid spec, etc), there isn't a downside except cost, and we know that the cost is repaid many times over in extended engine life. That makes it a good decision to change the engine oil. On the other hand, failures of perfectly well functioning automatics after a fluid change are well documented. I have seen them. I am not referring to transmissions that were on their way out, or where the wrong fluid was used. I am referring to the replacement of perfectly good (albeit aged and dirty) fluid with new fluid, containing a high concentration of detergents, and involving a change procedure than can move sediment from where it wasn't hurting anything (except our individual senses of what is right, ie it shouldn't be there) to where it can hurt something (a valve body, a check valve, an actuator). Incidentally, I have noticed that almost every time someone changes old fluid, they comment on the junk in the pan, as if that is justification for the change. That is where the junk is supposed to be. It is what the pan is designed for, to hold it. But failures after fluid changes happen all too often. It is a risk, not a large risk IMO, but a measurable risk. If the fluid is worn out, burnt, oxidized, etc, then it is well worth changing it (except that if the clutches are burnt, it is probably too late). But if there is no appreciable extension of transmission life to be expected from a change of a dirty aged, but serviceable fluid, then that risk of changing it becomes relatively more significant, and it is likely better to just leave it all alone.

The best maintenance strategies do not try to keep components like new. They try to keep them functioning as required, balancing cost against benefit.

I am not sure my own maintenance intervals should matter much, as they are based on my vehicles, driving conditions, fuel quality, etc, but to satisfy curiousity.....it depends on the vehicle and the application. This may be a little long and detailed. Also, this is what works for me. I am not Mike Miller, and I am not guaranteeing the results for others.

I have recently changed oil on a Toyota and a Civic (family vehicles) at 5000 km. Good interval for those engines IMO, they hold about 3.5 litres. My BMW experience ranges from a 318 (1994, spec'd at 16,000 km interval) which didn't make enough heat on my drive cycle to keep condensation out of the valve cover. It formed a paste, commonly seen. I drove 30 km to work, and it was a small and efficient engine, ie not much waste heat available to boil off the condensation. Changing oil at double the spec'd interval worked, ie 6000-8000 km. My E53 was spec'd by BMW at around 24,000 km (15,000 miles, modified by CBS). No condensation issues, same driving route. It got hotter, I presume. It also used a newer spec oil than the 318. I went to 6000 km (myself at home) and 12,000 km (dealer). I pushed that up to 8,000 and 16,000 with good results. With the 325xi, used on more short trips, I went 6,000 and 12,000. BMW did low mileage changes at 12,000 km on that one, despite them not being required until around 24,000 km. Z4 mainly sat in the garage waiting for sunny days, so it got very low mileage changes as I consider sitting to be harder on a vehicle than driving. Flash forward to the 535 and X3. Newer generation engines, newer generation oil spec (API SM). Haven't done any intermediate changes. Computer last called for service at 26,000 and 28,000 km, but I didn't let them go that long, closer to 22,000 and 24,000. No more short trips, they always get hot, and neither used any oil to speak of (1 litre at 12,000 km on the 535 IIRC).

Engine oil on the BMWs is from the dealer, or Castrol Syntec 5w-30. I have used Mobil 1 for top up, and have no qualms using it instead of the Castrol. Those are the only three oils I use on the BMWs.

I only use OE filters, no will-fit filters, no matter who claims to make them.

No automatics in the fleet now, but I haven't changed fluid in any of my last 8 automatic transmission vehicles. Last transmission failure was on a 1966 Mustang in the late 70s, and that includes many years of towing with SUVs.

Brake fluid every 24 months, rigidly adhered to.

I would change coolant at 4 years, but haven't had to for some time. It used to be every 2 years, some time back.

Manual transmissions and differentials, I used to use 50,000 km (generally more frequently than called for) but would now go 100,000 or 150,000 km. If there was a chance of water ingress (fording creeks, etc) I have changed fluids immediately afterwards. The BMWs don't ford creeks, the Fords did.

Transfer case used to be the same as differentials. With the reset required on the x drive on our X3, I am inclined to leave it to 100,000 then have the dealer do it, as I don't have the tooling to reset it.

Other maintenance: Air filters based on driving conditions, ranging from every two years to every three months (extreme dust). Brakes inspected twice per year when the winter wheels are installed, caliper ears lubed with HT grease, slide pins kept dry. Hub bores cleaned when tires are changed. Tires never rotated on the BMWs, even though they are off. Door hinges and latches greased annually (amazing how many don't do this). Full inspection underneath (any signs of leaks, everything tight, CV boots, etc) has been annual, but was every six months years ago. Spark plugs were every 5000 km on the Toyota, a little longer on the Honda, and I haven't touched them on any of the recent BMWs. I would think 100,000 or 150,000 km, but I don't have experience to base that on. I would inspect them at 100,000 km.

As to data, my own maintenance schedules start from the manufacturer's recommendations, and are modified from there based on driving conditions, my own historical results, ongoing monitoring and inspection, and my own experience and judgement. That is based on being a mechanic a long time ago (when we used fixed 3000 mile oil change intervals), and then several decades as a professional mechanical engineer involved in heavy mobile equipment maintenance. That maintenance involved oil and fluid sampling, guaranteed maintenance contracts over 60,000 operating hours, guaranteed fleet mechanical availabilities, lots of predictive techniques like vibration and performance monitoring, etc.

Told you it would be long. Sorry about that.

Jeff

[diesaroo]

Originally Posted by JCL

My wife insists on a manual transmission. Both our daughters drive manuals. I have owned lots of automatics (as many vehicles don't give you a choice).

While there is a chance of failure whenever maintenance is done, I don't equate an oil change with a transmission fluid change. If the oil change is done correctly (procedure, fluid spec, etc), there isn't a downside except cost, and we know that the cost is repaid many times over in extended engine life. That makes it a good decision to change the engine oil. On the other hand, failures of perfectly well functioning automatics after a fluid change are well documented. I have seen them. I am not referring to transmissions that were on their way out, or where the wrong fluid was used. I am referring to the replacement of perfectly good (albeit aged and dirty) fluid with new fluid, containing a high concentration of detergents, and involving a change procedure than can move sediment from where it wasn't hurting anything (except our individual senses of what is right, ie it shouldn't be there) to where it can hurt something (a valve body, a check valve, an actuator). Incidentally, I have noticed that almost every time someone changes old fluid, they comment on the junk in the pan, as if that is justification for the change. That is where the junk is supposed to be. It is what the pan is designed for, to hold it. But failures after fluid changes happen all too often. It is a risk, not a large risk IMO, but a measurable risk. If the fluid is worn out, burnt, oxidized, etc, then it is well worth changing it (except that if the clutches are burnt, it is probably too late). But if there is no appreciable extension of transmission life to be expected from a change of a dirty aged, but serviceable fluid, then that risk of changing it becomes relatively more significant, and it is likely better to just leave it all alone.

The best maintenance strategies do not try to keep components like new. They try to keep them functioning as required, balancing cost against benefit.

I am not sure my own maintenance intervals should matter much, as they are based on my vehicles, driving conditions, fuel quality, etc, but to satisfy curiousity.....it depends on the vehicle and the application. This may be a little long and detailed. Also, this is what works for me. I am not Mike Miller, and I am not guaranteeing the results for others.

I have recently changed oil on a Toyota and a Civic (family vehicles) at 5000 km. Good interval for those engines IMO, they hold about 3.5 litres. My BMW experience ranges from a 318 (1994, spec'd at 16,000 km interval) which didn't make enough heat on my drive cycle to keep condensation out of the valve cover. It formed a paste, commonly seen. I drove 30 km to work, and it was a small and efficient engine, ie not much waste heat available to boil off the condensation. Changing oil at double the spec'd interval worked, ie 6000-8000 km. My E53 was spec'd by BMW at around 24,000 km (15,000 miles, modified by CBS). No condensation issues, same driving route. It got hotter, I presume. It also used a newer spec oil than the 318. I went to 6000 km (myself at home) and 12,000 km (dealer). I pushed that up to 8,000 and 16,000 with good results. With the 325xi, used on more short trips, I went 6,000 and 12,000. BMW did low mileage changes at 12,000 km on that one, despite them not being required until around 24,000 km. Z4 mainly sat in the garage waiting for sunny days, so it got very low mileage changes as I consider sitting to be harder on a vehicle than driving. Flash forward to the 535 and X3. Newer generation engines, newer generation oil spec (API SM). Haven't done any intermediate changes. Computer last called for service at 26,000 and 28,000 km, but I didn't let them go that long, closer to 22,000 and 24,000. No more short trips, they always get hot, and neither used any oil to speak of (1 litre at 12,000 km on the 535 IIRC).

Engine oil on the BMWs is from the dealer, or Castrol Syntec 5w-30. I have used Mobil 1 for top up, and have no qualms using it instead of the Castrol. Those are the only three oils I use on the BMWs.

I only use OE filters, no will-fit filters, no matter who claims to make them.

No automatics in the fleet now, but I haven't changed fluid in any of my last 8 automatic transmission vehicles. Last transmission failure was on a 1966 Mustang in the late 70s, and that includes many years of towing with SUVs.

Brake fluid every 24 months, rigidly adhered to.

I would change coolant at 4 years, but haven't had to for some time. It used to be every 2 years, some time back.

Manual transmissions and differentials, I used to use 50,000 km (generally more frequently than called for) but would now go 100,000 or 150,000 km. If there was a chance of water ingress (fording creeks, etc) I have changed fluids immediately afterwards. The BMWs don't ford creeks, the Fords did.

Transfer case used to be the same as differentials. With the reset required on the x drive on our X3, I am inclined to leave it to 100,000 then have the dealer do it, as I don't have the tooling to reset it.

Other maintenance: Air filters based on driving conditions, ranging from every two years to every three months (extreme dust). Brakes inspected twice per year when the winter wheels are installed, caliper ears lubed with HT grease, slide pins kept dry. Hub bores cleaned when tires are changed. Tires never rotated on the BMWs, even though they are off. Door hinges and latches greased annually (amazing how many don't do this). Full inspection underneath (any signs of leaks, everything tight, CV boots, etc) has been annual, but was every six months years ago. Spark plugs were every 5000 km on the Toyota, a little longer on the Honda, and I haven't touched them on any of the recent BMWs. I would think 100,000 or 150,000 km, but I don't have experience to base that on. I would inspect them at 100,000 km.

As to data, my own maintenance schedules start from the manufacturer's recommendations, and are modified from there based on driving conditions, my own historical results, ongoing monitoring and inspection, and my own experience and judgement. That is based on being a mechanic a long time ago (when we used fixed 3000 mile oil change intervals), and then several decades as a professional mechanical engineer involved in heavy mobile equipment maintenance. That maintenance involved oil and fluid sampling, guaranteed maintenance contracts over 60,000 operating hours, guaranteed fleet mechanical availabilities, lots of predictive techniques like vibration and performance monitoring, etc.

Told you it would be long. Sorry about that.

Jeff

Maybe then you could tell me the secret to educating the female brain the fine art of cog swapping? But seriously, I feel the same as ard does regarding the value of your forum contributions. Also, I greatly appreciate the sharing of both your professional and personal experiences with vehicles and maintenance. I also follow a maintenance schedule very similar to yours on my vehicles with the exception of course regarding the transmission.

This is based on vehicles in my past and present ownership that the manufacturer has recommended the ATF and filter be replaced at specified intervals and my personal experience of trouble free operation when following this maintenance philosophy. My 1987 Mercedes 190DT even has a torque converter drain plug to allow for a more complete fluid change.

I have communicated with a ZF transmission repair professional and he is of like mind that regular fluid and filter changes enhance the performance and life of the transmission, and carry very little to no risk of causing component failure.

I don’t claim to be Mike Miller either and like yourself, my transmission maintenance philosophy has worked well for me in my experience and I shall continue to follow it rigidly unless I feel that in the future I have evidence to the contrary.

Eric

[Ghost-Flame]

Ardy and JCL,This thread has been fun to read. Who has that much time? But I thank you for the different perspectives.

I'm going to change my fluid today with M1 atf. This has worked great for me in the past, every 50,000 miles. Maybe I'm deluded but I think I'm extending the life of those parts that might fail that would lead to trans failure. But, That's just me and I also believe that at the end of rainbows are huge pots of gold.

[diesaroo]

Originally Posted by Ghost-Flame

Ardy and JCL,This thread has been fun to read. Who has that much time? But I thank you for the different perspectives.

I'm going to change my fluid today with M1 atf. This has worked great for me in the past, every 50,000 miles. Maybe I'm deluded but I think I'm extending the life of those parts that might fail that would lead to trans failure. But, That's just me and I also believe that at the end of rainbows are huge pots of gold.

Well that's all fine and dandy, and M1 is a good fluid for many applications, but I don't think the ZF unit in the X5 is one of them. Please do yourself a favor and get the proper ZF Lifeguard fluid for your tranny. Here's where I got mine The CTSC - ZF Parts

[jbond007]

...well if no one is tired yet and wants to read my saga and the fix, it's here.

Short version: 72,000 miles, partial fluid change with ZF LifeGuard6, new filter, new LURCH!, harsh shifting, mechanic reset adaptations, oil sensing settings, updated software for trans, shifts like a dream now. The end.

[Ghost-Flame]

Originally Posted by diesaroo

Well that's all fine and dandy, and M1 is a good fluid for many applications, but I don't think the ZF unit in the X5 is one of them. Please do yourself a favor and get the proper ZF Lifeguard fluid for your tranny. Here's where I got mine The CTSC - ZF Parts

Well Yes and no. My transmission is the GM, I have a 3.0. The fluid used by my dealer is any DEXvi. M1 is Dexvi

Also, I was reading my OEM BMW X5 manual last night. There is an owners manual that talks about owner operation, it said the trans fluid is lifetime fluid. It also has a maintenance BMW OEM manual that describes the maintenance items, It says that the ATF MUST BE changed every 100,000 miles. Yes it does. Pg 3 of the Service and Warranty Information book for 2002 X5 3.0i, 4.4i, 4.6is So for the folks that say you are doing possible damage when you change fluid, what do you say to the BMW engineers that say IT MUST BE changed every 100K.

"The following maintenance elements must be performed at the mileage/time stated(time intervals start from the production date).

-Brake Fluid... 2 years
-Engine Coolant... 4 years
-Oxygen sensor... 100K
-Spark Plugs... 100K
-Automatic TransmissionService: Change ATF every 100,000 miles"

BOOM

so If I cut that interval in half to 50K I'm doing a good thing