Transmission life. How to get the best?

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Leo

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I guess we all can acknowledge the fact that an engine would easily outlast the transmission in most cars.

So you'd think we'd be more worried about extending the life of our trannys than our motors?

So what could we do to keep our trannies from wearing out besides regular fluid changes?

Do different brands of ATF lower wear on the clutch packs? Do oil coolers make a difference on a passenger car? Magnefine filters worth it?

Just thought I'd like to see everyones thoughts..
 
I like to drain and refill 12-18 months. Most of my vehicles have drain plugs in the tranny pans. On the vehicles that don't have drain plugs, I'll have to drop the pan and change the gasket/screen. I've never had tranny problems by doing this and it's cheap insurance. On manual trannys, drain and refill the same way. Always use the recomended fluids.
 
A guy on my S10 ZR2 forum stated the following, which makes lots of sense to me and is what I go by:

quote:

There seems to be a lot of debate regarding when and how to service an automatic transmission, and what, exactly, a standard service consists of. Even though I'm not in the industry anymore, I was a certified diagnostician and tech in the automatic transmission repair industry and a service manager at a transmission shop. Here's my professional OPINION regarding automatic transmission service intervals and what's required.

Regarding service intervals… I’ve seen the most durable transmissions fail as early as 80,000 miles for no other reason than old, nasty fluid and a dirty filter. I’ve seen the most fragile of transmissions last 300,000 miles because they were serviced regularly! I recommend a normal pan/filter service (NO FLUSH) at 15k – 20k intervals for any vehicle that drives in mountainous terrain, tows a trailer, goes four-wheeling, or gets a lot of stop-n-go use. Vehicles that see mostly highway use in the mid-west can probably go as far as 30k/mi between services, but that’s the MAX!

It needs to be understood that ATF, whether synthetic or petroleum based, has several additives that make it perform is job correctly. There are FRICTION MODIFIERS that help the clutches grab (and release) when they're supposed to. There are VISCOSITY ADDITIVES that help maintain the "weight" of the "oil" for proper lubrication and hydraulic properties. There are DETERGENT ADDITIVES that help control deposits by suspending particles in the fluid until they can be filtered out. All of these additives need to be replenished from time to time, as they are "burned away" with normal use. The BASE oil in ATF doesn't really break-down the way engine oil does, so it doesn't really need to be replaced in its entirety, just refreshed. Five to Six quarts of ATF contain enough of these additives to ‘refresh’ the five to six quarts that remain in the torque converter and cooler lines when the pan is dropped. Therefore, it is not necessary to flush a transmission at normal service intervals.

A normal service STARTS with dropping the pan, which releases about 1/3 to 1/2 of the total volume of ATF. Only by dropping the pan can you replace the filter, so there's no way around this if you want to do a correct service! Once the pan is off, remove and CUT OPEN the filter! By examining the contents of the filter and the sediment on the bottom of the pan, an educated tech can accurately assess the condition of the transmission as a whole. It's ok to have SOME material in the pan and filter, but if you see any chunks (1/16" or bigger) of friction material or metal shavings, take the filter (contents intact) to an expert for evaluation, because you have problems. The little ½” circle of grey past in the middle of your pan is normal wear… Don’t panic, just clean it and continue with the service…

Modern automatics have a lock-up style torque converter that contains one pressure plate and one ring of clutch material. This clutch is very susceptible to overheating and slipping (anyone heard of the dreaded P1870 GM code?) and will start to crumble and shed material (that will end up in the filter and pan) if it starts to carbonize from heat. One preventative solution is to keep fresh friction modifiers (less slippage) and viscosity additives (better hydraulic pressure) in the fluid via regular maintenance.

Shops that suggest a flush and fill service instead of dropping the pan and changing the filter should be avoided. Shops that try to sell you a flush along with a pan/filter service at normal intervals are just trying to pay for their new flush machine a little sooner. A reputable shop typically charges about $70 to $80 for a service including bulk ATF, pan gasket, filter and labor. Chevy S-10 4x4’s usually warrant an extra ½ hour labor because the exhaust x-over pipe is in the way and needs to be moved, so be prepared to shell-out another $35 - $40 for that.

he likes amsoil fluid best of all, and another guy who chimed in on the thread had been using this procedure and had 298k miles on his ZR2's auto trans and it was still working fine with no rebuild.

I like ~30k intervals and theyve done lots of people well. An AT is one item that has been sensitive, and doesnt seem to be getting more robust as they design new ones... Probably doesnt hurt to keep the peace of mind, given the increased complexity and cost as they get "better".
 
I've seen that post before and it remains my favorite opinion on transmission services. Keep it simple. Periodic filter replacements and fresh fluid are your best insurance.
 
JHZR2 wrote:
quote:

..........I like ~30k intervals and theyve done lots of people well. An AT is one item that has been sensitive, and doesnt seem to be getting more robust as they design new ones... Probably doesnt hurt to keep the peace of mind, given the increased complexity and cost as they get "better".

Excellent post.

I agree with ATFCI of 30k. However, for my use of Ford AX4N transmission, I would modify his procedure for a complete machine fluid exchange using Mobil 1 Multi-Vehicle ATF every 30k and full service filter change every 60k.
 
All the boys at F150.net forums know that you GOT to change the ATF at least every 30K, unlike the manual that says 100K, if you expect the 4R70W to make it to 100K miles.
 
In addition to regular maintenance I think that a transmission cooler is one of the best investments you can make. I've had one on every automatic that I've owned since the mid-80's and never had a transmission problem. My wifes Cherokee has had a cooler on it (as well as regular maintenance) since new and it's at about 160K. Still shifts like it did from day one.
 
Transmission coolers, high quality ATFs, regular change intervals, transmission sump increases, known software and hardware updates, and extra filtration will go a long way to extending the life of the transmission.

You need to research the history of and the weaknesses/updates in the transmissions that you own.

It also helps to have a good transmission from the factory and no-teenage drivers!
 
Three ways:

1) Drive Gently

2) Avoid towing whenever possible

3) Change the ATF at the OEM recommended interval for severe service, using an approved fluid or upgraded synthetic fluid.

50K is a reasonable service interval for the newer ATFs on the market today. More frequent ATF changes do not increase longevity, they're merely for an increase in shift quality and piece of mind.

quote:

All the boys at F150.net forums know that you GOT to change the ATF at least every 30K, unlike the manual that says 100K, if you expect the 4R70W to make it to 100K miles.

Yes, you do, if you use the truck for towing. Otherwise, there's no need to, unless you're experiencing shudder or shifting problems.

By doing such frequent fluid changes, all that you are obtaining is piece of mind...
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quote:

2) Avoid towing whenever possible

Towing isn't something like "between meal snacks". You either need to do it or you don't. It's not like leaving a few tools in the bed that you don't need to lug around.
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Interesting that noones said anything about synthetic ATFs? Nevertheless I try not to run through the gears like a manual and take it easy whilst the car is cold.

Seems 30k OCIs are the go. So what about those filled for life trannies like in BMW?
 
Leo

The debate over lifetime fill centers around the question: "whose life?"

Long-life fluids last longer than regular fluids, but in the end the gearbox will last longer if you change the fluid than if you don't. I suppose it may last so long that you sell or crush the car before it wears out so you never get the benefit, but that logic sounds far-fetched to me.

Cheers
JJ
 
I'm telling you from experience on the 4R70W transmission, you got to change it out at least at 30K, I don't care what your doing to it. They have all developed the dreaded shutter about that time but most people don't think it's the transmission, just "one of those" things.
 
Leo wrote:
quote:

Interesting that noones said anything about synthetic ATFs?

erm...I did.
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Mobil 1 Multi-Vehicle ATF are full PAO synthetic ATF. Also, I believe Amsoil ATF are as well.
 
Keeping the fluid cool and clean will make a large difference in the life of an automatic. My heavily abused 4R100 has over 100K with syn fluid and 30K drains (pan and converter). I can't avoid towing whenever possible, when I need to tow something I need to. Towing will not hurt the transmission as long as you drive sane and keep the ATF temp to a reasonable number.
 
I can only say what has worked for me.
Fluid changes once a year,(works out to be about every 30k) with pan drop and filter replacements have gotten me:
1994 Cavalier, over 200k.
1995 Villager, same.
1995 Chevy K1500 149,000, current.
1997 Sunfire, same.
2000 Focus, current, 111,000.
All on original trans, all shifting and running well when sold or traded. I think 1040 wrecker says it best- keep the fluid clean and cool for a longer life.
 
IMO, the best way to get max trans life is stay away from the makes/models with finnicky transmissions/transaxles. A minimum of a couple pan drops and filter changes will definately enhance the lives of some, but many (if not most) of the failures are due to poor design. All the clean, cool ATF in the world wont stop them from failing.

G/luck
Joel
 
quote:

Originally posted by JTK:
IMO, the best way to get max trans life is stay away from the makes/models with finnicky transmissions/transaxles. A minimum of a couple pan drops and filter changes will definately enhance the lives of some, but many (if not most) of the failures are due to poor design. All the clean, cool ATF in the world wont stop them from failing.

G/luck
Joel


Couldn't have said it better.
 
The best, single thing you can do yourself to extend the life of your vehicles' automatic transmission or transaxle is regular fluid changes.

This cannot be stressed enough. A good general recommendation for all vehicles is 20K-30K miles or 1 year. It's safe, possible overkill for certain applications, but given the current costs of automobile repair work, its good insurance.

Being smarter, asking a transmission repair professional (not a franchised talking head/service writer) about your specific vehicle would be one way to get an experienced recommendation. We know the specific failures, normal operating specifications of certain designs and could advise (again) to your specific application.

It's true some transmission designs are not as destructive on the ATF and therefore can go longer w/o change.

Regular fluid (filter changes depend on the specific vehicle) changes will help prevent seal troubles (internal/external), lubrication related failures, excessive bearing and bushing wear, and friction/clutch damage.

As previously suggested, additional cooling is the next tool to help keep your vehicles' transmission on the road working properly. Most modern vehicles' automatic transmission cooling is inadequate, but this is rapidly changing with some makes and models, so again being educated about what you are buying or own is the best way to know what you should do.

I agree with the S10 ZR2 crossposting. Good, competent shops who perform transmission service work will always remove the pan (flush or not) at least to inspect during a service. Not all transmission designs have removable drainpans nowadays, so again back to specific applications.

BTW, the only vehicles (lately) i've seen the automatic transaxle outlast the engine are the 90-93 Honda Accords. Most of those around my part of the world are pushing 250K+ w/ 2nd engines and original transaxles.
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It's disappointing to see Honda recently barely keeping up or falling behind against domestics when it comes to AT durability.
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DH
 
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