Automatic trans

[blacksnapon]

All of these can cause late or delayed upshifts, EXCEPT: 1) A faulty vacuum modulator 2) A worn oil pump 3) Misadjusted shift linkage 4) A sticking governor

 

[6L PWR]

#1 - That's my "guess".

 

[O'Rattlecan]

governor...

Ryan

 

[mrfixit]

I vote #2; A transmission doesn't have an oil pump, since it uses FLUID, not oil. The oil pump in the engine would have no effect, unless, of course, it is so low the engine siezes...

 

[slmann]

I'm going with #2.

 

[mrfixit]

Just to clarify my post I should say that a transmission DOES have a PUMP, just not an OIL pump. The pump is in the bell housing behind the torque converter in most every model.

 

[surewhynot]

My guess is 3

 

[Fellro]

2, as the line pressure will be affected on all valves, not just upshift valves. The governor pressure would be lowered the same amount as the shift valves.