42RLE has started banging when downshifting out of overdrive: What's up with that?

WLDRIDE

WLDRIDE

WLDRIDE
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SouthCentral Colorado
My auto trans has started banging when downshifting out of overdrive. It happens both when I'm driving in overdrive and am coming to a stop, and when I depress the O/D Off switch. I don't know if this could be related in any way, but I just had all the fluids changed: transmission fluid, transfer case, front differential, and rear differential.

Thoughts?
 
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Did they fill the transmission with the correct ATF+4, no other ATF is correct, and have you checked its level yet? The engine has to be running while doing that.
 
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WLDRYDE said:
Jerry, I will check on that. So the wrong transmission fluid can make it shift hard like that?
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I don't know that the wrong ATF caused your particular problem but the right ATF is critical to the proper operation of an automatic transmission. In our Jeep transmissions, the only correct ATF is ATF+4. If it doesn't say ATF+4 in big letters on the front label it's the wrong stuff. Nope, not even Mobil-1 ATF is correct.
 
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Jerry Bransford said:
I don't know that the wrong ATF caused your particular problem but the right ATF is critical to the proper operation of an automatic transmission. In our Jeep transmissions, the only correct ATF is ATF+4. If it doesn't say ATF+4 in big letters on the front label it's the wrong stuff. Nope, not even Mobil-1 ATF is correct.
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Well, at least according to the paperwork they gave me, they did put ATF+4 in it. So that's not the culprit (although I will check with them on Monday to be sure that's what they actually put in it).
 
WLDRYDE said:
Well, at least according to the paperwork they gave me, they did put ATF+4 in it. So that's not the culprit (although I will check with them on Monday to be sure that's what they actually put in it).
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That's good, in the mean time you can check its level via its dipstick. Remember that the engine has to be running while you check the transmission level. Shift through the gears a couple times then put it back in Park before checking the level.
 
Jerry Bransford said:
I don't know that the wrong ATF caused your particular problem but the right ATF is critical to the proper operation of an automatic transmission. In our Jeep transmissions, the only correct ATF is ATF+4. If it doesn't say ATF+4 in big letters on the front label it's the wrong stuff. Nope, not even Mobil-1 ATF is correct.
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Jerry, here's the end to the story (at least I hope it's the end). The brand new transmission oil filter from NAPA had a hairline crack in it (I'm amazed the mechanic found it), and it was sucking air. That caused the Jeep to throw a code and things got out of whack (my paraphrase of actual events). They replaced the filter and did a reset. Thankfully, it was all warrantied by NAPA.
 
Surprising but good news! I can't figure out how it could suck air with a cracked filter but I can't quite remember the 42RLE filter configuration like I can the 32RH which is completely immersed in ATF.
 
Jerry Bransford said:
Surprising but good news! I can't figure out how it could suck air with a cracked filter but I can't quite remember the 42RLE filter configuration like I can the 32RH which is completely immersed in ATF.
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This is what the filter looks like:
Screen Shot 2019-11-18 at 3.29.27 PM.png


There was a tiny crack in the plastic near the round orifice with the red seal on it. In the end, I think that the need to do a re-set was a blessing. It's shifting better than ever now... smooth as silk. And all paid for by NAPA!
 
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I‘m pretty sure the 42RLE filter is completely submerged in fluid. I recently changed my filter and fluid. I had left the dipstick in while doing it. I seen it hanging down from the valve body and noticed that I could only see a little bit If the dipstick. The part that was sticking through was a little less than half the distance between the 2nd and 3rd hole on the dipstick. The 3rd and 4th hole, where the Full Hot range is, was not visible at all, but that’s where the fluid level is correct when you check it.
 
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Wldride: I have the same issue (changed filter, now bangs coming out of OD). I did not find a defect in filter but replaced it anyway. Now I have same issue again with new filter. What brand filter did you put in that solved the issue ? Were there other theories as to what it might be ? Thanks in advance.
 
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