late 3-4 upshift

[sunfish32]

i have a 1986 300e with a 722.3 transmission. I have a fairly good upshift from second to third but i seem to have a very late upshift to fourth like it won't happen until 3500+ rpm. Just recently i replaced the vacuum modulator and the new modulator holds vaccuum and receives good manifold vacuum. I have made some cable adjustments which helped to bring the 2-3 upshift back into the proper range but they did not seem to affect the 3-4. does anyone know of a good printed or electronic transmission manual that could help me troubleshoot this tranny? i have the microfiche but they are unbearable to work with and very hard to read. the transmission shifts firmly into third but late into fourth but i get a good shift when finally occurs
HELP
MIKE

[C32AMG]

If the transmission has a long 2 -3 and or 3 – 4 up shift at light and partial throttle, the K1 and /or K2 clutches are slipping, do to excessive clutch clearances on high mileage cars.

[sunfish32]

Its not that the duration of the shift is excessively long but rather the timing of just the 3-4 shift is late and sometimes allows the engine to rev to redline before allowing the shift to occur. The quality of the shifts themselves once they happen are very good quick and firm no flaring slipping or anything like that. I currently have removed the valve body and i am checking for dirt build up and worn parts because the microfiche service manual that i have said that might be an issue. I will let you know how i do. Could the k1 band not be engaging at that giving me this problem as well thanks
MIKE

[C32AMG]

Full throttle kick down up shifts are the only time any up shift should happen at red line or just below. From your description the 3-4 up shift is a slip. The K1 and K2 are clutch drums

There are MB valve body up date springs for a delayed 3 -4 up shift. I need the all of the numbers stamp on the passenger side transmission rail, just above the pan. To see if it applies to your transmission

[sunfish32]

i was finally back underneath the car but i forgot to get the numbers off the side i will ge that as soon as possible thanks for your help
MIKE

[sunfish32]

124 270 06 01 722 320 02 810116 is the number posted on the side of the transmission casing. I did some testing and found that i have no governor pressure intermittantly. What i mean is when the upshift doesn't happen the pressure gauge doesn't move but when the pressure gauge moves (which was rare on a 10 min or so test drive, the pressure was within parameters (greater than .5 bar at 30 kph) I think i should add that i have been trying to remove the governor on my 1986 300e and not having much luck. I pulled off the cover and have the removed the support so the tranny is lower. the problem is i can't release the governor retainer because i can't find it. What i understand is that it should either be a lock nut on the passenger side of the tranny, which isn't there, or it should be a clip in the drivers side, which i can't see if it is there or not. do i need to pull the pan down? i also found a great link which has a sort of transmission manual posted in pdf for the 722.3 /4/5 http://transmission.articles.mbz.org/akp722.pdf
thanks in advance for any help
MIKE

[C32AMG]

If you mean on the 3 to 4 shift you have no governor pressure or intermittent it’s because the K2 drum has an internal leak or the K2 plastic piston in the valve body has a crack.

When doing oil pressure test always start with working pressure, all pressures derive from it. Next is modulating then governor.

The release for the governor is on the rear pump; look at page 50, fig. 42 of your link. They call it the axial retainer nut. Remove the 10mm nut and turn the screw CCW to release the governor, turn it CW when you install it, the slot in the screw should be in a horizontal position; locked.

[sunfish32]

thanks for your reply. since my last message i have removed the the tranny for a complete rebuild after i took out the the governor and it had no noticable problem. About a week ago i realized that the problem was deeper than previously thought. I was losing all my upshifts sometimes. If i punch the throttle real hard sometimes it would upshift sometimes not. I tried driving it with the kickdown switch disconnected...no change in condition. there were no problems when i took out the valve body and looked for damage. I haven't owned the car long and i bought it with this problem. the first time i changed the fluid it was far and away the worst i have ever seen sludge at the bottom of the pan was very thick almost like body filler before it hardens anyway the rebuild kit is comming and i should have it apart soon i will let you know what i find. thanks
MIKE

[sunfish32]

i have been in the process of rebuilding my 722.3 trany i have found that the clutches in both the k1 and k2 were completely worn to nothing. one of the friction discs managed to get warped and stuck to the shaft making it difficult to remove the clutch pack as a whole. i had to take the circlip off the pack before removing the clutch. other than that i have found nothing other than dirt and build up no doubt caused by neglect for years and years. the Reverse clutches weren't too bad and the bands b1 and b2 had very little wear. i am about one third reassembled and will likely finish this afternoon.

[DieselDon]

I have been having the same problem with my newly aquired 1987 300td with 210,000 miles on it. I'm curious how much of a job it was for you to do the rebuild and whether you needed special tools or not. I don't need details of the procedure, just a seat of the pants sense of what I might be getting into.

Thanks