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Symptom - hard 1st to 2nd gear shifting when warm, at times a secondary(delayed) bump is felt. All other gears shift very smoothly up and down, down through second too. Sometimes it will shift three for time OK and the same amount of times hard(random). Throttle control can lessen the hard shift.

Motor mounts have been replaced and inspected - good condition

I have done 3x drain and fill routinely so I assure you the fluid is good - Honda fluid used

Stall test Cold 2400 rmp D, 1, 2, and reverse

Stall test Warm 2100 rmp D, 1, 2, and reverse - TC is getting week

WOT take off from 1, no observed slippage

WOT take off from 2, no observed slippage

No clutch slipping observed in any other driving conditions.

With the exception of shift solenoid A, all other linear and shift solenoids have been removed, tested, and cleaned. There was absolutely nothing found in the screens and no sludge.

One observed issue:
Shift solenoid A ohms out OK but has transmission fluid in the electrical connector. Of course this is the one that the starter needs to be removed to replace. I'm not changing shift solenoid A in a attempt to fix the shift problem, but rather because it is failing.

I'm curious if you have any other ideas. I hate to rebuilt this original transmission with 411,000 miles because of one issue.
 

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Prime suspect would be the 1-2 clutch pack seals leaking and/or worn disks. I don't have the factory service manual anymore, but I believe that testing pressures at the external pressure taps can confirm this.
 

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I wouldn't suspect warn clutch discs unless it was slipping once in gear. "Hard shifts" tend to indicate that the clutches are still doing their job, but being commanded to do it at the wrong time.

If it was my MDX, I'd do two things...

1) I'd install a magnetic filter in line with the transmission cooler lines. This will trap some of the metal bits that can otherwise end up in the bores of your shift solenoids (since they are electromagnets), and...
2) Put in the suggested amount of LubeGard Platinum additive. I haven't ever been a fan of "liquid fixes" for transmissions, but this does seem to help. My son's Subaru tranny had lots of really bad behavior. A fluid drain and refill and a bottle of LubeGard had it shifting like it should again. The LubeGard Platinum helped get a buddy's 2nd generation Odyssey from "scary" to "nearly perfect". Worst case, it doesn't do anything, and you're out $15.
 

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Discussion Starter #6
[
2) Put in the suggested amount of LubeGard Platinum additive. I haven't ever been a fan of "liquid fixes" for transmissions, but this does seem to help. My son's Subaru tranny had lots of really bad behavior. A fluid drain and refill and a bottle of LubeGard had it shifting like it should again. The LubeGard Platinum helped get a buddy's 2nd generation Odyssey from "scary" to "nearly perfect". Worst case, it doesn't do anything, and you're out $15.[/QUOTE]

I may try that. Like you, quick fixes are not my "go to" but with all the miles I have the worse it could do is finish the transmission or best it would shift better for a while longer. I'm prepared to put a new transmission in at this point anyway. I just wanted 500K out of it..we'll see.
 

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I've read so many good things about the stuff, and seen it work well for two cars myself (taking one from not doing anything right to essentially perfect), that it's kind of a no-brainer. I bought a big bottle of the stuff last time so I can share it with friends when necessary, or at least have it on hand for my own cars should they act up. Let us know how it goes...
 

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Hi, sorry for getting in the old thread, tried to find the right thread but no success.
My 05 MDX runs well, no lights, no slipping, it shifts hard from I guess 3rd-4th or could be 2nd-3rd gear. It will lock rev hard to end and then changes the gear with a slight bump/push. You don't feel it powerless or slipping. I mean it supposed to shift to next gear at early rev but it will shift hard at last rev taking the current gear fully to the end. Any idea about the issue?
Thank you
 

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I'm really trying to interpret that post. I THINK that the symptom described is a shift flare, where the car accelerates properly in 3rd (for example) but then feels like it slips into neutral for a second or two before shifting into 4th. If you don't let up on the gas when the transmission is flaring, you'll get a very harsh shift (bump). If you do let up, the transmission will shift softly and no harm will be done - you could drive like this for many thousands of miles without hurting anything, other than your patience.

How many miles on the vehicle? What is the history of transmission fluid changes?
 

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I'm really trying to interpret that post. I THINK that the symptom described is a shift flare, where the car accelerates properly in 3rd (for example) but then feels like it slips into neutral for a second or two before shifting into 4th. If you don't let up on the gas when the transmission is flaring, you'll get a very harsh shift (bump). If you do let up, the transmission will shift softly and no harm will be done - you could drive like this for many thousands of miles without hurting anything, other than your patience.

How many miles on the vehicle? What is the history of transmission fluid changes?


I assume your reply was to my recent post.
As I understand slipping is something like you missing a gear, and you feel powerless when the gear is slipping? But here it seems opposite, no feeling of a missing gear or getting into neutral mode, it just goes on more than usual in the same gear to the end (it should shift early) then changes to next gear with a bump/push.
It's just like if you driving a manual vehilce and take the 2nd gear to full end/rev and then suddenly shift to the next 3rd gear. You can say it's a delayed shift but no feeling of neutral in between.
I sell cars so have no idea about the history, 160k miles, I haven't shown it to a mechanic. Just got it yesterday. Thanks for understanding.
 

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I'd check the condition of the fluid. And heck, even if it looked pretty good, I'd do a drain-and-fill (three quarts of Honda fluid). That tends to fix a host of issues, as will ensuring that the fluid level is correct (it's measured with a fully warmed-up transmission with the engine shut off for 30 to 60 seconds).


If new fluid at the correct level doesn't fix it, the most likely mechanical culprits would be the shift solenoid C, or the pressure control solenoid valve B. That's assuming that the problem is the 2-3 shift.
 

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Can I add the fluid throught the dip stick hole with a narrow funnel? I don't have tools to get through the bolt, and the fluid is low, I don't want to drive it to the mechanic before filling it as that may damage the transmission further. Thanks
 

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Yes, you can use a thin hose and funnel to fill the fluid through the dipstick tube. It takes a little longer, but there's no other down side, and I do it that way to prevent the potential for more debris getting in the transmission while I'm fiddling with the fill bolt. You definitely don't want to drive with seriously low fluid. I'd say that if you have any questions about the fluid level (which is common) you should just pull the drain plug, and check it for accumulated metallic bits on the magnet - then just add three quarts. That'll pretty much put the fluid at the right level, though it would still be a good idea to do a check the right way when you have the opportunity (to park it on a level surface, and check the level within 60 seconds of shutting off the engine).
 

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My mechanic filled up 3 qts properly after draining it today. It drives good now, there is still very slight delay from 2-3 shift but that feels only when you rev it hard, otherwise it shifts smooth and normal and no bump anymore. I assume that almost 80% of the problem is solved. The mechanic said that the fluid was very dark and muddy which is not a good sign though, he said if the fluid change didn't fix the issue then it could be the clutch but after a test drive I saw a big difference, atleast the bump is gone. But the fluid level is little above than the second/top dot on the dip stick now which I may fix with a little drain.
 

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Sha31, great news on getting 90% better with a single fluid change. I'd still recommend doing at least one or two more drain-and-fills, since that will remove almost all the nasty old fluid that was in the transmission. The first D-N-F will only replace about half, the second takes it to around 75%, and the third to near 90% new fluid. New fluid is the best insurance you can buy for an MDX, since the transmission is the weak link in an otherwise impressively reliable vehicle. And the truth be told, the trannies aren't really all that bad, only in comparison to the rest of the vehicle.
 

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It still has the delayed/hard shift from 2-3 when rev it hard, if rev it gently then it shifts normal. Yeserday the fluid was showing higher on the dip stick, today it was showing lower than the level, I added 1 qtr and it's showing again little above than the level (fluid level was checked always when vehicle was warmed up and then shut off). So that's the confusing part. Lubegard additive will be a good idea? If so it has just to be added on top or the same quantity of transmission fluid has to be drained to?
 

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I'd suggest adding less than a full quart, looking for that perfect level. Better yet, do another drain-and-fill, and put in three quarts. Yes, if it was mine, I'd add 8 ounces of LubeGard Platinum (that won't take it over the limit). That will give you not only any advantages of the LubeGard, but the advantages of cleaner fluid (which is always, always, always a good thing on a Honda / Acura).
 

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Symptom - hard 1st to 2nd gear shifting when warm, at times a secondary(delayed) bump is felt. All other gears shift very smoothly up and down, down through second too. Sometimes it will shift three for time OK and the same amount of times hard(random). Throttle control can lessen the hard shift.

Motor mounts have been replaced and inspected - good condition

I have done 3x drain and fill routinely so I assure you the fluid is good - Honda fluid used

Stall test Cold 2400 rmp D, 1, 2, and reverse

Stall test Warm 2100 rmp D, 1, 2, and reverse - TC is getting week

WOT take off from 1, no observed slippage

WOT take off from 2, no observed slippage

No clutch slipping observed in any other driving conditions.

With the exception of shift solenoid A, all other linear and shift solenoids have been removed, tested, and cleaned. There was absolutely nothing found in the screens and no sludge.

One observed issue:
Shift solenoid A ohms out OK but has transmission fluid in the electrical connector. Of course this is the one that the starter needs to be removed to replace. I'm not changing shift solenoid A in a attempt to fix the shift problem, but rather because it is failing.

I'm curious if you have any other ideas. I hate to rebuilt this original transmission with 411,000 miles because of one issue.
Hi,

Sorry if this response is too late but I thought I would post this just incase it helps anyone.
I have a 2017 MDX and from the time I picked it up until now, I experienced a hard or "jerky" shift between 1st and 2nd gear. I took it into my dealership for 2 years, explaining the problem but was told that was how it was. They did do a "re-learn" which was supposed to help the car adapt to my driving but this did little to elevate the problem. I knew that I wasn't dreaming because they once gave me a curtesy 2018 MDX and if shifted perfectly.
Eventually I spoke to the Service Manager and he said that they performed a "Running software update" and this completely fixed the problem. He said that the technician would only find out about this update if they were looking for specific things otherwise they wouldn't be alerted to it. Anyways, after driving the car now I can tell you that it shifts perfectly between 1st and 2nd gears and I am completely happy.
 

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Could also be the shifter cable not lubricated enough. Have you checked that? After all this time, could just be dry.
 
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