BIC2

2012 MDX Advanced, 56k miles. For the last, maybe 10k miles, have intermittent issue going up hills. Closet thing to describe it is lugging engine, but it's not lugging, pinging or knocking in the traditional sense. Only use Premium Top Tier gas.

It does seem like it might be slightly in too high a gear and the RPMs fluctuate up & down about +/- 200 RPM. If I give it some gas to downshift, then it's happy in the lower gear. I wonder if it's a transmission programing thing? Thanks.

Chopperpilot

When was the last time the transmission fluid was changed ?

BIC2

@Chopperpilot , at 28,700 miles (Dec 2017), Acura dealer did "Transmission Service on SHAWD." Been less than 5 years and about 27,000 miles since last transmission service.

Chopperpilot

I’d check the transmission dipstick for level and reddish color , if it’s brown and stinks ..I’d would drain and refill at the minimum.

altair47

"Transmission Service on SHAWD." - sounds like they changed the fluid in the rear diff.

BIC2

@Chopperpilot @altair47 My father-in-law owned the car before me. Acura did do the rear dif along with the trans service at 28,700. Vavoline did front & rear dif at 34,000 (Sept 2019). He probably didn't realize he only had 7,000 on the rear dif fluid.

Checked tran fluid. No easy task on this vehicle. They want you to check one minute after turning car off. Takes 5 minutes to get dipstick back in. Anyway, fluid color looks OK. A thin film runs about an inch or so higher than the full mark. But, the fluid isn't thick enough to fill the Hi/Lo holes on the dipstick like motor oil does. Is that normal or am I actually below the dipstick? Thanks.

Chopperpilot

A 2012 MDX with low mileage as yours absolutely needs OEM Honda transmission fluid ..period !

If you’re spending 5 minutes to check the fluid level and the ‘condition’ of the fluid , you may want to have someone drain and refill ASAP

note : I’ve owned 12 Honda/ Acura vehicles… used aftermarket ATF on a 1997 Accord…not to good ..OEM FLUIDS only .

BIC2

@Chopperpilot The transmission fluid is Honda, apparently the diff fluids are from Vavoline.

The 5 minutes to check the fluid is to get the dipstick back in the hole. Although after a few cycles, may have gotten it down to 3 minutes.

My comment on the condition of the fluid was that it doesn't fill the Hi/Lo holes as fluid seems too thin for that compared to the Hi/Lo holes filling on engine oil. Is that normal? Thanks.

csmeance

Fluid is thin and can be hard to read. Use a large flashlight ot help you guide the dipstick in and a helper to turn off the car. Remove dipstick, clean, reinsert and you should have a level between the two dots. In addition, the clean paper towel should show a BRIGHT pinkish red color.

The 6spd transmission in these era of Acura's tear up trans fluid. I've found changing the trans fluid every other oil change has helped 99% of my trans issues. I use Acura/Honda DW-1 fluid, about 3-4 quarts per change.

Also with your era of MDX, NEVER go past 5K miles on an oil change and change 1x a year, do not exceed that time frame. Also be sure to check your oil level every time you get gas. With low miles, you can easily take minor steps to prevent oil burning.

BIC2

@csmeance Thanks for those tips. What about the dif fluid, how often and does it have to be Honda fluid?

csmeance

For the transfer case any gear oil will work as long as it's the correct weight. For the rear diff, you want to use ONLY HONDA/ACURA DPSF:

altair47

On my own behalf, I’ll add that in 2007-2010 MDX wrote in the user manual that for the rear differential use a ATF-Z1 only, but in 2011 Honda switched to the DW-1 and therefore they began to pour DPSF into the rear diferential. My opinion is that everything with ATF-Z1 tolerances can be poured into the rear differential. I use Liqui Moly ATF1200. This is not an advertisement

BIC2

What about mileage for transfer & rear dif? Owners manual doesn't really say, only gives symbols. Is there a symbol translation chart available? Thanks.

BIC2

Brought it to my local Firestone. They have a former Honda tech that has worked on my MDX before replacing shocks & timing belt..

Replaced transmission fluid with Honda DW-1, let it drain for an hour and put in 4.5 quarts

Replaced transfer case with GL-4 75W-90 (not sure what brand but they generally use Pennzoil)

Replaced differential with Honda Dual Pump Fluid II (same part # 08200-9007 as Acura DPSF)

Reset Transmission Control Module

On the 10 mile drive drive home, seems the issue has been fixed. Thanks.