DANG! It all of a sudden started to suddenly pull away from a stop sign in 2nd gear. It won't downshift into 1st gear when I come to a stop. If I come to a stop and pop it into Neutral and then back to Drive, it'll start in 1st gear just fine. It just won't "pull down" into 1st when I come to a stop. Nothing else has changed on the car. I adjusted the vacuum modulator all over the place, and the shift points changed on the up-shift, but it still won't pull down. If I goose it on the take away it'll drop into 1st gear and then shift OK. But if I just crawl away from a stop it'll start in 2nd. Vacuum is where it always has been, about 16" at idle, with the needle bouncing a little, but I attribute that to the cam. Yes? HELP!
Jeff, It's the governor. Take it out, and spray it down with some gumout. Lube it back up with ATF, and reinstall it. Mark De Conti puts an extra spring in his governors to avoid this problem. He did mine. PM him(dcm422), he can tell you how.
IT WAS THE VACUUM MODULATOR. ALL FIXED! Replaced it with a new one and we're good to go. Odd thing though, the governor was frozen stuck solid as a rock too.
99.99% of the time it is the governor. The modulator may affect it as as it creates pressure to overcome governor pressure and downshift the trans. What is supposed to happen is that when the Gov stops spinning its internal valve is bottomed and pressure is exhausted. If the Gov sticks (as you said), then there is still some pressure on the shift valves which can keep them open in turn keeping the trans in a higher gear. Hopefully you cleaned out the Gov and freed the valve and your problem is solved. When I modify a Gov, I will use 4 coils of a spring that fits between the internal valve and the plastic gear. This insures that the Gov valve slides to the exhaust position and the trans goes into 1st gear. It is kinda tricky to get the spring installed correctly if you have not done this before. You need to make sure the spring is not too stiff and that it does not lay over as the valve is installed. See how things go and if you need Gov modified, please let me know. Take Care, Mark
Mark, I'd like to send you a stock governor and have you modify it. Do what you have to in order to up the shift points to as close to 5000 RPM as you can get, and do any other mod to it you can/want - including the extra springs. If you're interested, where do I send it and how much $$$? Yards
1-2 @ 5500 RPM, 2-3 @ 5400 RPM. I had to change my valvebody to a later design( 1971). My Transmission is a 1967 BT out of a big car. The 67 switch pitch valvebody was curtailing my 2-3 shift to about 4300 RPM. After changing to a later valvebody, and messing with the governor weights and springs, I had success. It was fun taing it out on the Saw Mill Pkwy for testing her out. Mark DeConti helped me out with the valvebody(From Bruno D), and the governor adjustments. We used the Readers Digest Shop to change the valvebody(thanks John). Also the 67 valvebody had no 3-2 valve, so I only had a full throttle kickdown. The later valvebody gave me a part throttle kickdown. Now, I can pedal it at 35-40, and it will kickdown without me getting into the secondarys. Having problems Steve?
I don't get a 1st gear kickdown. Nor a part throttle kickdown. Has to be WOT. It is a PAE trans. Hmmmm. Looks like I need to make a call to Jim in the morning.
Jeff, I'm not taliking about a 1st gear kickdown necessarily. If i'm in 2nd gear at low speed, I can get a part throttle kickdown. If it's in third, it will go to 2nd part throttle. I have to be going really slow to get a 3-1 kickdown, and sometimes it won't do that either. The Stage1 BB's would go 3-1 just for an instant, then shift up. Drove Carl Rychlik's Stage 1 once. Matted it at 40 MPH, it dropped down to 1st, and almost immediately shifted to 2nd. Wish my car would do that, but it has to do with the special 1-2 valves those BB's came with.
The trans-go kit that JW sent me had a replacement valve that I changed out to allow me to downshift into 1st from 3rd at about 40mph. And yes, it is only there for a second or so, then shifts into 2nd. It's really fun to do that, though:grin: I'm not really sure about the 3-2 downshift at slow speeds...I installed a spring in the modulator valve that made a quicker 2-3 shift, and I don't like it. I just haven't pulled it out to get rid of it yet. Lazy, I guess.
Yeah, I know that's what you meant Larry. I also mentioned that I don't get a part-throttle kickdown as well. It never really bothered me before. With the torque and HP I have, and the 3.42 rear, I don't need 2nd gear much when I'm cruising. My buddy builds transmissions like I mentioned, and I'm going to take his spare TH400 short-tail and have him build it up for me. I'm talking low 1st gear, HD sprag, high-tech clutches and bands, new front pump. The works. We'll swap it this winter. Ooooooo, a new winter project! heh heh...
Thanks Larry mine shifts about 5000 but till i get new posi i can't tell much. i'll have to look in to new governor and valve body. Anyone you know around here good with t400 sp
Steve, Was your trans converted to SP, or was it originally so, like mine? Unless you have the 65-67 SP valvebody, you don't need to change it. Just modify the governor. It's easy, just time consuming with the test and tune. You need the B&M governor kit. http://www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=15697&prmenbr=361 I can help you with it one weekend. It will be fun.
My old tranny used to hang up in second a lot............when I instaled the 73 valve body, I haven't had the problem since. Also, I polished the governor valve by hand with some scotchbrite before I put it back together....maybe that helped? Anyway, those '65-'67 VB's really suck.......mine will downshift from 3-1 from 45 MPH now with the newer VB........and as long as I have it floored, the tires crack loose on the 1-2 shift :Brow:
I'm going to install a new valve body. I have a sticky valve somewhere... So, can someone please post a step by step instruction for R&I of a valve body on a TH400??? THANKS!
Hey Jeff.I guess you will also take a run at that rear main seal when the trans is out?? :TU: Later,Tony.
