reasonable "particle count" Acura auto trans?

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Apr 25, 2010
Ballwin, MO
What would a reasonable particle count be on an Acura 5 speed automatic transmission in a 2003 MDX with 137,000 miles? If no specific info for this transmission is available, what is considered a reasonable or acceptable particle count number in an automatic transmission in general? Is there a number or numbers that would indicate an immediate need for service and transmission fluid replacement? Any info will be much appreciated. I just got a particle count analysis and can't find any standard by which to interpret the results. The over 21,000 for the smaller than 4 microns number seems on the face of it to be extremely high.
Not a whole lot of people do a UOA on there transmission, post the report on here.
The most desirable particle count is something specific to each manufacturer and not easy to find. I did a lot of research and found that in the early 2000s the general industry standard was an ISO code (2 numbers) no higher than 19/14. Lower is better. Why don't you type up that particle count and ISO code so we can look at it. Based just on a 21,000 ct < 4u, it's not horrible but let's wait to see the rest. I think you are a good candidate for an external (cooler line) filter. Usually, the fluid will condemned for contamination before the fluid is degraded. With good filtration, you can then run the oil until it's reached a condemnation point via TAN or some other oil-based issue. Here is are tests done on some of my Fords for context. This one done a few thousand miles after a fluid exchange. ISO Code (3) 18/17/14 >= 2 Micron 3257 >= 5 Micron 1206 >= 10 Micron 334 >= 15 Micron 129 >= 25 Micron 30 >= 50 Micron 3 >= 100 Micron 0 Here's another 400 hundred miles after installing an external trans filter to the oil above. Some 15K miles have passed since and I will soon have another test to publish. ISO Code (3) 15/14/11 (2-code= 14/11) > 2 micron- 407 > 5 micron- 150 >10 micron- 42 >15 micron- 16 >25 Micron- 3 >50 micron- 0 >100 micron- 0 Here is another some 2200 miles after the filter ISO Code (3) 13/12/9 (2-code = 12/9) > 2 micron- 101 > 5 micron- 37 >10 micron- 10 >15 micron- 4 all others 0 Here's another done by a different lab at a different time before any oil was changed or filtration was done. The trans had about 12K miles on it from new. ISO Code (3) 21/18/14 4-6u- 1,005,050 6-14u- 167,340 14-21u- 5,539 21-38u 2,616 38-70u- 154 >70u- 0
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