I replaced my Transmission mounts last week, but this week I have noticed rough downshifts from 4 to 3 + rev hang, going through all Gears UP is fine.

I am 2000miles from my next Transmission Fluid change.

Any advice to remedy the problem?

 

Interesting. Does it jerk hard when downshifting?

I have a weistec built trans and after few years of it working amazing, i noticed last year from 4th to 3rd it jerks hard as if something is about to break, and makes a weird ping / pop noise while downshifting 4 to 3.

Cars in the shop getting complete upgrades plus fluid swap , and hopefully it fixes it.

 

It jerks hard, and the revs hang. It’s not a consistent issue. it happened on Saturday and sunday but hasn’t happened since.

 

Make sure the car is fully warmed up. Mine does the same thing if It isn't warm yet, it does a harsh/clunk shift from 4th to 3rd. Even if the oil temp is in the white color, it can still shift hard. If you live in warmer climate, for oil temp, 195°F+ should give you a normal shift. If it is a cold morning or day, I would wait till 210°F+.

 

could be low on fluid...could be your engine tune...could be a cold transmission...

if not any of those...i'd recommend bringing your vehicle to a repair shop that has STAR/DAS to run diagnostics. the system will report of any delayed shifting per gear and how many occurrences.

 

I noticed mine did this a few times with spirited driving today. Here in FL, the oil temp was 220F when it happened so I can't say the car wasn't warm. I'll have to keep an eye on it, but sure enough it was the same from 4th to 3rd gear.

 

If you drive spiritedly or brake harshly it will hang gears when down shifting. Transmission and engine mounts will have nothing to do with it unless they weren't tightened. Low fluid causes weird stuff. Transmission service is a preventative maintenance item. Changing fluid, unless it's burnt from really high temps or degraded will not fix or resolve a mechanical issue. Aka my cars transmission is slipping.... I need a transmission service.... hey you just serviced my transmission and it's still slipping lol.

 

Mine does the same, jerky in the 4th to 3rd downshift, it is only when braking hard to a stop as it rips down the gears in D or S, normal driving it is fine and it is fine in manual to downshift. I thought it was OK, no clunking or anything, maybe I will get it checked out.

 

do the MCTs fix this? Because it is quite annoying especially during braking

 

Are you tuned? It seems that MCT cars that are tuned experience clunky downshifting on decel pretty frequently. Mine does this from time to time. I also have a suspicion that ROW boxes might be a factor as well, but I'm too lazy to swap them back and check.

 

ROW boxes will not affect shifting. the other thing you mentioned will.

 

Only reason I am suspecting the ROW boxes is that the clunky shifting feels like the car is intermittently not rev matching on downshifts. My suspicion is the different MAF metering as compared to the OEM box could be a factor considering the high LTFTs that ROW box users have reported.

 

Fluid change eliminated the problem entirely.

 

you were probably low on fluid then. when the 722.9 is low on fluid it can exhibit hard shifting and shifting hanging between gears longer than it should.

 

I have been having this same 4th to 3rd hard downshift and it is getting worse. It is only on forced downshifts, worse in S+ and M. Car is fully warm, fluid change was about 20,000 miles ago, Eurocharged tuned and ROW’s, and has not been driven hard. It’s like what Balanbro was saying- the car does not rev match downshift it just slams into 3rd. Was thinking of switching back to factory tune to see if it helps. Have you tuned guys went back to factory tune to see if that makes a difference?

 

My issue was present prior to tune, after tune and even tried reverting back to factory tune, issue remained. My fluid was low, about 600ml its a pain in the *** to check but it improved my shift quality considerably once topped up.