M1009 Hard Shifting tranny, first post

[ralbelt]

Thanks Kip, already have one, did not install yet.

 

[charlietango]

I put all the old stuff back on and she is shifting back to the way it was before I started. very strange but I think what happened was the plastic reducer on line #5 off the T (firewall side) broke when I changed it so I forced the smaller line onto the bigger fitting. I think it caused some sort of collapse of the sidewall or something at the junction. I will have to go source out the reducer nipple at parts source or something and try again. It is shifting at (well what the speedo reads but is im sure inaccurate) 35 to 2nd and 45 to 3rd . It didnt always do this it used to shift to 3rd around 35-40 if I recall. I have to manually slap the shifter around from 2nd to drive and it will often go in to 3rd before 45 when I do that.

I am going to change the fluid and filter, run some seafoam through it to clean the valves. also going to change the fuel filter out.

on a side note but possibly related the oil breather return line on the passenger side (rubber part that goes 90 degrees to the intake) is horribly cracked! I am not sure if that is a vacuum leak...? I need to see if the parts store has those too.

can someone PM me Doghead's add? cant search by user and not sure what he has to search by item.

 

[IROC99]

Early shifting

Myy M1009 shifts out of 1st early, hurting acceleration. Will shift a little later if pedal is on floor board, but not much. My vacuum line comes up from engine and goes directly to line back to transmission, bypassing a black modulator on the top right side of engine. What does that modulator do and is it ok to bypass this?

 

[chief1983]

Uhm, it sounds like someone decided to bypass the vacuum regulator module on the injector pump? I suppose since no vacuum means late shift, full, unregulated vacuum would mean very early shift. You're probably going to want to fix that and reattach it with the proper connection, going from the vacuum pump on the back of the engine, to the regulator on the IP, and then to the transmission vacuum modulator. One of the TMs, -34 or -20 covers that in detail.

 

[cmroles]

Myy M1009 shifts out of 1st early, hurting acceleration. Will shift a little later if pedal is on floor board, but not much. My vacuum line comes up from engine and goes directly to line back to transmission, bypassing a black modulator on the top right side of engine. What does that modulator do and is it ok to bypass this?

Running it in that condition is not going to do nice things to the transmission over time. The TH400 will last longest with positive, firm shifts (not slamming, but firm). The low rpm / slow shift will accelerate tranny wear. This is similar to excessively slipping the clutch in a manual when you shift.

If you don't have a vacuum gauge you can do the "trial and error" method for vacuum valve adjustment. Just rotate the valve all the way to the firewall and test drive. If its shifting too early, rotate the valve forward just a little bit and try again.

After adjusting this way I got a nice solid 1st-2nd shift at around 20mph, and my 2nd-3rd at about 35mph at moderate throttle....perfect!

 

[caladin]

Thanks for the info!

 

[chief1983]

cmroles, your avatar made me lol, because I've used that same type of stepladder for that purpose.

 

[kentuckycucv]

Ditoon new vacume lines... Mine were rotton... now she shifts great.

 

[winslows]

I put all the old stuff back on and she is shifting back to the way it was before I started. very strange but I think what happened was the plastic reducer on line #5 off the T (firewall side) broke when I changed it so I forced the smaller line onto the bigger fitting. I think it caused some sort of collapse of the sidewall or something at the junction. I will have to go source out the reducer nipple at parts source or something and try again. It is shifting at (well what the speedo reads but is im sure inaccurate) 35 to 2nd and 45 to 3rd . It didnt always do this it used to shift to 3rd around 35-40 if I recall. I have to manually slap the shifter around from 2nd to drive and it will often go in to 3rd before 45 when I do that.

I am going to change the fluid and filter, run some seafoam through it to clean the valves. also going to change the fuel filter out.

on a side note but possibly related the oil breather return line on the passenger side (rubber part that goes 90 degrees to the intake) is horribly cracked! I am not sure if that is a vacuum leak...? I need to see if the parts store has those too.

can someone PM me Doghead's add? cant search by user and not sure what he has to search by item.

Did you ever replace the rubber block? Mine seems to be cracked and I was wondering if I could bypass it. I can't find a replacement part for it either.
Edit: It wasn't really cracked, just starting to so I coated the exterior with Gorilla Glue, the real problem was a 4 inch crack on both sides of the vacuum line between the pump and the modulator....

 

[lindyp38]

heres what fixed my bad transmission slipping...i replaced the hose..and transmission works fine..