Manual transmission becomes hard to shift in stop-and-go traffic - why?

[masospaghetti]

M5OD transmission in my 2000 Sport. Shifts fine most of the time, but if I am in really slow traffic (where I am putting it into gear and taking it out of gear frequently, without moving much) the transmission becomes almost impossible to shift, taking a lot of physical effort. I tried 1st-5th and reverse, all feel the same.

I just changed the fluid to standard Mercon V which did help shifting most of the time but did not affect the condition I noted above.

What could cause this? It almost seems like a lubrication failure (since the transmission is a splash-type lubrication system that requires movement to lubricate).

Thanks all!

 

[Flash]

Maybe it's your arm getting tired.

Or you clutch master or slave cylinder might be tired and with frequent use in a short period the effort on the clutch fork may be reduced making the gears a bit sticky.

You know how like with a worn brake master cylinder the brakes will still work but if you rest your foot on the pedal fluid will get past the seals and the pedal will slowly drop to the floor.

 

[Beargap]

The clutch slave cylinder is failing. Check the fluid level, topping off might help, but the slave cylinders fail at about 100K miles (I know, 3rd one on my '97 with 300K miles).

 

[Micky.D]

I'd also check oil level, as low oil will heat up faster , these are common for leaking up the top of the box , the 3 rubber grommets.

Cheers
Mike

 

[koda2000]

The clutch slave cylinder is failing. Check the fluid level, topping off might help, but the slave cylinders fail at about 100K miles (I know, 3rd one on my '97 with 300K miles).

most likely this... even if the fluid level is fine.

 

[my98nnj]

If the master or slave was failing, you'd notice a change in clutch engagement position relative to the pedal travel.

OP - Is this the case?

 

[masospaghetti]

The clutch engagement position doesn't seem to be changing.

I don't quite understand how the slave cyl could be causing this issue. In stop and go traffic, I am repeatedly pushing the clutch pedal. It would make sense, if I was holding the clutch pedal down, that the pressure would gradually bleed off with a bad slave.

 

[Steve Hearn]

I have same trans. new clutch and slave with 2000 miles. the work was performed by master mec. he re- inspected and re- adjusted and found zero leaks, low levels etc. as
above 90 percent of time everything perfect then wham. Locked in gear, somtimes truck wants to move forward with clutch depressed. Much pressure to do anything, then perfect for a spell. I live in the country with no traffic. Oh and this is a 2wd with 190.000 miles and is perfectly maintained.

any thoughts