Viewfinder88

First off, thanks for reading and for any input. I would very much appreciate it.

Bought used. Did not notice this until a little while later. Seems to have gotten much worse as of lately.

Auto transmission. 80K miles.

Apparently the transmissions downshifts specifically at 37 mph from 5th and 25mph from 4th. I can clearly tell because of harsh shift down and the RPM kicking up right about 500rpm every time. And while in 4th and 3rd gear, the car will drag and decelerate noticeably on its own. It's somewhat noticeable in 4th as I let it coast to downshift to 3rd at 25mph where the rpm would kick up and continue to decelerate very noticeably down into around 15mph where it would 'release.' I will also hear a very faint rumbling/whirring noise just before it lets up and goes back to normal which gets louder as it's about to 'let up' or 'release.'

What's worse is that this is somewhat intermittent and is very apparent in the city in heavy traffic where I'm constantly shifting between 3rd and 4th. When I get out to where I'm usually in 4th, even when the problem does present itself, it's less apparent. This has made it problematic for car mechanics to diagnose.

Also, there's a dip and pause when acceleration sharply when the car has to downshift to accommodate the sudden demand for torque followed by a sudden jolt.

When driving the car 'normally' it's just an annoying thing to always feel but when I need to switch lanes when there's a sudden hazard on the highway and have to match the speed of the cars behind me, I fail to be able to match their speed in time and become a hazard myself.

Additionally, shifting to neutral when I feel the drag relieves the problem entirely even when shifting back immediately into the same gear. Even when it downshifts from 4th to 3rd, as long as I don't apply the gas, it downshifts perfectly smoothly. When the problem isn't prevalent, the RPMs stay at a smooth-coasting 1 to 1.2rpm, but when I apply any torque and let it coast, it hangs at around 1.5 and the car starts to sharply decelerate on its own.

I've been told TLs can be 'touchy' and that this may be 'normal' but I can't believe it. It feels terrible to drive and maybe I'd be convinced if it was like that all the time but sometimes the car shifts just fine but most of the time it drives like crap.

This is likely a transmission issue but a very general conclusion. I'm hoping someone here can make any recommendations or offer any additional information as to fixing this issue. I'm afraid that this is going to be tough to prove to an adjuster to get a replacement trans or at least a rebuild.

At this point, it's probably apparent that I'm not exactly a car buff but if you have any questions, please ask because I'm not sure If I'm being as clear as I possible could be.

Thank you for your time.

polobunny

Your numbers are right, that's the speed it downshifts...

I would do a 3x3 drain and fill of the ATF and pressure switches while at it. Hope for the best. The TL automatic transmission is notorious for being flaky, although 07-08 are better than 04-06. You can read a lot about this on these forums.

The sooner your fix it the better. You might be able to save it from killing itself, or least mitigate the issue.

Viewfinder88

Thanks for the reply.

The speeds at which it downshifts don't bother me. It was just to show how precisely I can tell what the speeds are just because of how it shifts.

And about the fluid, I should have mentioned, it has already been replaced with specific Honda trans fluid in attempt to fix the problem but with no difference whatsoever. Although I have to admit I'm not sure what 3x3 is and if my mechanic did that.

Also by 'fill of ATF switches' you mean fill up? I'll look into it.

Thanks again.

polobunny

I mean 3x3 drain and fill of the ATF
AND
replacing the pressure switches/solenoid

The 3x3 pertains to the way of doing the drain and fill. Honda automatic transmissions should not be completely flushed at once but rather remove 3 quarts, fill 3 quarts, make sure the new fluid mixes with the old one, then remove 3 and add 3 and so on.

Get informed on the procedure your mechanic used and the quantity that was removed and then added.
The pressure switches/solenoids are used to engage 3rd and 4th gear and when they are out of spec the shifting can seem very harsh.

csmeance

The transmission + torque converter hold 9 quarts of fluid. The pan only contains 3-3.5 quarts at any given time. This means that only 1/3 of the fluid can be replaced via a traditional drain and refill method. Thus came the 3 x 3 fluid change. You change the fluid 3x with 3 quarts of fluid. You drive between the fluid changes to circulate the fluid. Most places know this and try to sell you a "power flush" that uses chemical cleaners in the trans. This method is specifically barred by honda as the chemicals damage the clutch packs.

The newer way is to disconnect the line from the transmission cooler and hook it up to a machine that collects the old fluid and pushes the new fluid via the line so there's no loss in fluid or pressure. You can do this method at home by routing the drain line into a bucket and draining about 3 quarts of fluid. Refill the trans via the filler bolt with 3 quarts and repeat until the fluid that you get coming out is as pinkish red as the fluid you put in, usually 3 times.

The transmission uses pressure switches to control how it shifts, replacing the 3rd, and 4th gear pressure sensors with new ones every 50K is recommended. Also these cars do have an internal transmission filter that is a little bit of work to get to. I'd highly advise replacing it too every 100K at a maximum, maybe 30K-40K minimum. The fluid should be changed via the old 1/3rd method at least every oil change starting at 30K.

DW-1 fluid is much cheaper if you buy a case, 12 quarts, at a time. It's like $80 at my local honda dealer.

Viewfinder88

Thank you. This is all very useful information.

As soon as I get a chance to do these things, I'll be sure to report back if it helps.

Viewfinder88

Can the pressure switches and solenoids be replaced without having to 'crack open' the transmission?

I was told that in order to rebuild the trans, it would require to cut in half what is encasing it as it is 'internal.'

Slpr04UA6

The Pressure switches are not within the trans, here is thread with part numbers and a list of instructions on how to change them yourself.


https://acurazine.com/forums/third-g...-08-tl-840630/

Cramos056

did you ever try out these suggestions. did you feel any difference ?