Acura MDX failed transmission UOA - Z1 - 125000 mi

[youdontwannaknow]

This is the UOA of my mdx transmission that failed and was rebuilt.
Started with transmission slipping then flaring and then hard sudden involuntarily downshifts.
Clutch packs were worn. Dont know anything specific about the condition of the TQ but it was replaced.

I am second owner of the car and I know anything after 50k miles was Z1 with the last drain refill done with DW1. Wouldn't know for sure what used prior to 50k.

 

[pbm]

Poor A/Ts are the reason that I won't shop Honda again.
The Honda Z1 fluid is nothing special from what I can gather....I'd use Redline D-4 or Amsoil.

 

[440Magnum]

Aluminum from wear from the torque convertor? Really? Is that a Honda thing, or is it just Blackstone playing fast and loose with words? I've never seen aluminum in a TC. That's a heat-generating dynamo that is made of steel... often heat-treated steel. The only thing I could think of is the TC lockup clutch... but... REALLY?!? When I see aluminum wear metals in an AT, I immediately think that the CASE is getting chewed up by a failed bearing or other component grinding against it.

Sorry for your expense, but honestly I consider 125k pretty good for a car or car-based SUV / light duty auto transmission these days. The real trucks (Ford, Chevy, Dodge, Tundra) are getting much better AT life than they did 15 years ago, but a lot of the front-drive based stuff seems stuck at sub-200k lifespans just like 1992.

 

[OtisBlkR1]

im planning to trade our Accord for just this reason, the tires are getting worn down and that 100k water pump timing chain service will be due.. so thats a easy $1,500-$2,000 right there for those items.. and even though im particular with the tranny in this car and service it often.. im not going to trust it past 125,000 miles.. then i will be out another $3,000 so im just anticipating $5,000 out of pocket.. Id just rather put that money on a newer model payment and not have the stress of worrying when these parts will [censored] out...

 

[Hokiefyd]

This is one reason I don't care for Honda's OEM ATF. That fluid sheared heavily. Starting viscosity is around 7.5 at 100*C. I do have a few questions:

1) Are you saying that your last drain/fill before failure was with DW-1? Did you perceive any difference in transmission behavior with DW-1, and did the slipping occur also with the older Z1 in it?

2) DW-1 was in your transmission when it failed? But this UOA is of Z1, right? How long was this fluid in the transmission, and how long after you installed DW-1 did it fail?

General comment: the zinc concentration in your first UOA looks low for genuine Honda fluid. It is possible that the previous owner or even dealer had used something different. My local Honda dealer doesn't even use Honda fluid when servicing these.

 

[cchase]

Originally Posted By: OtisBlkR1
im planning to trade our Accord for just this reason, the tires are getting worn down and that 100k water pump timing chain service will be due.. so thats a easy $1,500-$2,000 right there for those items.. and even though im particular with the tranny in this car and service it often.. im not going to trust it past 125,000 miles.. then i will be out another $3,000 so im just anticipating $5,000 out of pocket.. Id just rather put that money on a newer model payment and not have the stress of worrying when these parts will [censored] out...


For what it's worth an Accord of your vintage isn't one of the "known weak ones".

 

[Mr Nice]

Quote:
General comment: the zinc concentration in your first UOA looks low for genuine Honda fluid. It is possible that the previous owner or even dealer had used something different. My local Honda dealer doesn't even use Honda fluid when servicing these.


What ATF does the Honda dealership use ?

 

[Donald]

Originally Posted By: 440Magnum
Aluminum from wear from the torque convertor? Really? Is that a Honda thing, or is it just Blackstone playing fast and loose with words? I've never seen aluminum in a TC. That's a heat-generating dynamo that is made of steel... often heat-treated steel. The only thing I could think of is the TC lockup clutch... but... REALLY?!? When I see aluminum wear metals in an AT, I immediately think that the CASE is getting chewed up by a failed bearing or other component grinding against it.

Sorry for your expense, but honestly I consider 125k pretty good for a car or car-based SUV / light duty auto transmission these days. The real trucks (Ford, Chevy, Dodge, Tundra) are getting much better AT life than they did 15 years ago, but a lot of the front-drive based stuff seems stuck at sub-200k lifespans just like 1992.



My Camry has high aluminum in the UOA, even with a Magnefine filter. But the car kept on going and going. Sold it at 224K running fine. Amsoil ATF.

 

[Clevy]

Didn't Honda use 10w-30 in their trannies at some point in time. I can't remember if it was Honda or another japanese automaker.
The Japanese still use motor oil in the shared sump motorbikes though and they seem to last forever.
Dunno

 

[Quest]

Originally Posted By: Clevy
Didn't Honda use 10w-30 in their trannies at some point in time. I can't remember if it was Honda or another japanese automaker.
The Japanese still use motor oil in the shared sump motorbikes though and they seem to last forever.
Dunno


up and until the mid 90s: Honda M/T gearbox lube can be substituted with 10W30 multivisc motor oil. From that point onwards, because of additive changes in motor oil, replacing M/T box lube with engine oil no longer provides enough protection (Mola can conform this part).

I'd rather use the proper kind of lube (Honda MTF) in my M/T box instead of substituting with engine oil.

ATF for Honda is a different story .

Q.

 

[youdontwannaknow]

Originally Posted By: Hokiefyd

1) Are you saying that your last drain/fill before failure was with DW-1? Did you perceive any difference in transmission behavior with DW-1, and did the slipping occur also with the older Z1 in it?

Answer to your questions in order -
Yes.
No.
Nothing other than a rare rumble strip type shudder at 20-25mph and low acceleration. It may or may not be related to this failure hard to tell.

Originally Posted By: Hokiefyd

2) DW-1 was in your transmission when it failed? But this UOA is of Z1, right? How long was this fluid in the transmission, and how long after you installed DW-1 did it fail?

Yes. Because it only drains like 1/2 of the fluid so its like part Z1 part DW1 in there so not sure what I'd call the overall fluid. It failed about 18-19k after the DW1 was put in.


Originally Posted By: Hokiefyd

My local Honda dealer doesn't even use Honda fluid when servicing these.

Very Interesting. What exactly do they use ?

 

[Hokiefyd]

Originally Posted By: youdontwannaknow
Originally Posted By: Hokiefyd

My local Honda dealer doesn't even use Honda fluid when servicing these.

Very Interesting. What exactly do they use ?


They use Valvoline MaxLife ATF. They say that there are no warranty issues as long as the fluid is spec'd for Honda transmissions. But they also say that they very rarely see transmission failures anymore. This is coming from a dealer, so they may be trying to guard Honda's reputation; I'm just reporting what they told me on the phone (after I asked about a drum in the shop with a Valvoline MaxLife ATF label).

I'm using that very product right now in our MDX. I like it much better than the DW-1. Ours had objectively slower/looser shifts with DW-1, especially as the concentration of it in the transmission (as it mixed with the older Z1) increased over time with more fluid changes. It really slipped the 1-2 shift bad one hot day after an interstate jog and that weekend I drained/filled twice with the MaxLife ATF and it's much better since.

DW-1 ran similarly "loose" in our CR-V as well, but the Valvoline was a tad too firm for my taste in that car. I'm using Castrol Transmax IMV in it. I'm sold on aftermarket fluids in Honda transmissions.