New trans won't downshift to 1st

[WE4]

These pressures are not right..

Pressure at minimum TV in park or neut at 1000 rpm should be 56-64 pst at max TV 173-198
in rev at 1000 should be 105-118 and 322-369
in d4 and d3 at 1000 should be 56-64 and 173-198
in d2 and d1 at 1000 should be 123-138 and 123-138

Hey eight sec , thanks for the input but I think your numbers are a little off. However ,after days of screwin with this guys problem I do agree that High line will cause but that is not this guys problem. He has a gov feed problem in the plate, I think.We will know in a few days. But those pressures are off. Rev in a stock or slightly modified trans will not exceed 250 psi.and Low should be the same or within 10% or reverse. We like to see 220 -240 or so at full tv in OD. This will always work well..

Bruce
WE4
www.PTSnctb.com

 

[EightSecV6]

I got the pressure #'s right out of the GM service manual for a BRF coded 2004r, oh well I guess it could be a misprint??????
We recently repaired a freshly rebuilt trans with the identical problem, someone had changed the boost valve in the pump and had the line pres. too high. If you shift to N and back to D or put it in L1, you exhaust the governor and it will start out in first, isnt this what the trans in question does?
Hopefully you guys get it straightened out with the plate change but if not, I would suggest taking a look at the pres. reg. valve. Good luck!
Bill

 

[WE4]

LOL

Bill, I think you are right about the misprint as we see it all the time. I guess their quality control on publications is as good as their quality control on building the trans itself.. LOLOLOL

Thanks for the help......

Bruce
WE4
www.PTSnctb.com

 

[transfixleo]

Larger boost valves won't affect idle pressure since you (shouldn't) don't have Modulated TV sent to it yet unless the TV setting is wrong. This should also increase the force holding the valve downshifted too but it could explain higher than normal minimum pressure. Try this: To adjust the TV Cable skip the book method and do this: Press the 'D' shaped lock button on the adjuster and loosen the cable setting (The black housing that the metal cable is in will move forward). Now, have someone floor the gas pedal while you check to see if the throttle plate is open all the way. Usually they are off a little and will wiggle. Do whatever you have to do to get it open solid. Now, with the pedal still floored, press the 'D' button and pull the cable casing (the black tube) back as hard as you can (putting maximum tension on the metal cable) and release the button. You now have the engine, tranny and gas pedal all in sync at WOT. Mark the cable casing so if for some reason it gets moved you can know where to put it again. The problem with the 'self adjust method' is that it bends things and puts them permanently out of whack. It is also the full TV setting, which is theoretically what the GM method does.

 

[TrboHead]

Nightmare....

Squeez87,
This is the same exact nightmare I went through a couple of years ago. No 1st gear after coming to a stop. I feel your pain......
This is what I did.
I pulled my transmission twice to have the rebuilder go through it twice. Before I purchased and bolted in a brand new VB from GM, I messaged the 1-2 valve and checkec for debris, checked the line pressure in all gears, pulled the governor a bunch of times, loosened retighten VB bolts to proper spec, loosened retighten VB to my own spec(Barely tight at all), used a new VB gasket, even tried using NO gasket at all!!!!
I finally bought a new GM (X) spacer plate untouched by any tranny guy except myself now that I have been babtized in the red stuff manny times over.

Problem solved.......

Hope you put in that new spacer plate soon. If that aint it, I would be very supprised.

Just another Buick Nut,

Larry
"One Buzin Half Dozen"

 

[squeeze87]

FIXED!!

Installing the plate from Bruce did the trick! Had one set back which was that the trans would lock up in manual 3-2-1. Removed valve body and replaced with my original BRF and that did the trick! Car downshifts to 1 every time and shifts great. The lock up problem may have been due to contamination, a messed up check ball or who knows what, at least it works now!
Overall, I would say if i knew then what I know now, I would have had it done by Bruce. The car runs now, but i had to pull the trans and totally tear it down again because i forgot the low clutch apply ring (no reverse), changed valve bodies 3 times,and had more dexron on me than I care to think about! Thanks again to everyone who responded and especially Bruce who actually helped me over the phone while driving yesterday. Anyone who needs a trans should give serious thought to PTS, I mean jeez, how many places would help out the way he did for someone 3000 miles away who hadnt purchased anything from him?

 

[ApullinV6]

"Before you remove the valves, stroke them with a scrribe and make sure that they are not physically sticking. If they are, you may have some foreign debris in there"


I helped a guy install a shift kit in his car and it was doing the same thing. When you pulled out of the garage it would be in 1st but once you went through the gears it would never drop back down, unless you manually done it. It would drop down to 2nd but thats it. It ended up being a valve that was hung. Once removed and reinstalled it started shifting find. I'm not sure what valve it was, being my only trans. job but best I remember it was about 3/4 to 1" long about 1/2" in dia. on one end and 1/4" in dia. on the other. Kinda like a plunger type deal.

Hope this helps,

 

[ApullinV6]

Opps didn't see the fixed page.

Glad you got it fixed.

 

[GNSCOTT]

I posted this same damn problem about 6 months ago. Everyone wanted me to bring them the tranny to look at, so instad of spending a minimumof what $400 to have someone look at it, i practically gave away a newly rebuilt hi po tranny for a little above a core charge

 

[TurboMike]

I have the same problem on a customer car except it only does this when cold. After it's warmed up it's ok. It's all new, all billet.

 

[squeeze87]

On my car, it turned out to be the seperator plate, when someone starts messing with the governer feed hole, this is what can happen. I installed one from Bruce and the problem was solved!

 

[77 cruiser]

How`s your line press. hot & cold I had a problem like that & I had high press. was getting full line all the time. Just a shot, good luck.

Jim