Hard 1-2 Shift

[terminator0723]

On my 94 Ranger, in 1st gear it revs up to a decent rpm then when it shifts it jerks the crap out of you. It gets better the longer you drive the truck, but it's still there. Any idea what's going on here?

 

[gotmudd]

On my 94 Ranger, in 1st gear it revs up to a decent rpm then when it shifts it jerks the crap out of you. It gets better the longer you drive the truck, but it's still there. Any idea what's going on here?

i'm assuming that we're talking automatic transmission, in which case you should have a "vacuum modulator". if this is the case it will be on the back of the transmission on the passenger side w/a rubber line from it to a steel line going to the motor w/another rubber line connecting it to an intake vacuum port. make sure that the rubber hose connecting steel line to motor and rubber line connecting steel line to modulator are connected and not cracked or brittle. if they are good then replace your modulator [cost @$15] it sounds to me like you are not building enough vacuum in transmission. if lines are good check modulator by pulling hose off of modulator at transmission and check to see if fluid runs out, there should be NO fluid leakage.

 

[MAKG]

That would explain late shifts.

Hard shifts at the correct RPM points to other problems (like the valve body).

 

[terminator0723]

Yeah, sorry. It's an auto. Ill check out that modulator when it decides to stop raining here.. Thanks!

 

[gotmudd]

That would explain late shifts.

Hard shifts at the correct RPM points to other problems (like the valve body).

not sure but i had same problem on my F250 and when i changed the rubber lines and swapped out the modulator the problem went away

 

[Bruce]

Check to make sure the vacuum line isnt broken, pinched, or unhooked also. I have seen the vacuum port on the manifold plug up too also line sucked shut.

 

[VaGent]

That would explain late shifts.

Hard shifts at the correct RPM points to other problems (like the valve body).

I checked with the head transmission guy at FORD as I had this very same problem. He told me the problem was with the governor valve located in the tail stock of the transmission. I bought the governor from FORD & replaced it myself & it stopped shifting hard when the transmission was cold.

Mine would only shift once I got the RPMs up to around 3500-4000 & then shift very hard when I first started out from my house. It would only do it once & then it would shift great. Since I changed the governor valve, I've not had anouther problem with shifting at any time. The hardest part of the job was dropping the transfer case, drive shaft & unbolting the tailshaft housing oin the tranny to get to the governor. Repalcing the governor itself was the easy part of the job.

 

['94RangerXLT420]

i had the same problem the ither day after i put the motor back in and it was the vacuum line to the modulator. It came off the modulator valve and went back on. I hate that heat sheild covering the modulator. When i replaced mine i went through the floor in the cab so much easier than crawling under the truck.

 

[CTswampyankee]

I would try to fix it soon. my old 94 auto shifted into 2nd hard an after a wile it snapted the 2nd gear band. so i had no 2nd gear at all. Not fun!!!!