700r4 Not Shifting...

[Ashton84W]

Hey great knowledgeable people's of the world! So I have gots a problem. My truck ain't shifting. 1984 K10. I've looked everywhere: forums across the net, YouTube and some friends. I'm stuck. So here's the deal: I have 1st, Neutral, Reverse and Park. Since I have reverse- it's not a cracked sunshell. I can shift through the colum so I haven't burned out any bands. Now I know there is 3 most likely scenarios causing the transmission not to shift. 1) Improper TV Cable adjustment/ stretched cable. 2) Governor Gear is Striped. 3) Stuck TV Valve inside the transmission.

I've taken the Governor out 3 times. The weights move freely, the gear shift and the little metal price inside moves freely. So my Governor is good.

I've pulled the TV Cable quickly many times to try and unstick the valve (if it is stuck). No change...

I've replaced the TV Cable with one from AutoZone. Now here is where it gets weird- the Cable will not self adjust. When pulled, the slider does not pull out and does not ratchet. I can manually set it buy pushing the "D" shaped button and pull out the slider till it's tight at WOT. It did the same thing on the other cable except the plunger was set back all the way to the bracket leading me to believe it was stretched. Anyways point being; it didn't self adjust, I had to do it. Still no change...

I need help. Any suggestions? I have a max of about 35 mph and can't feel any shifts in OD. What should I do about the cable? Should I drop the pan (big mess and waste of newish fluid) and change out the filter and look at the TV Valve? What is my next step? Any help would defiantly be welcome and MUCH NEEDED!

 

[1987 GMC Jimmy]

Hmm... I think the TV cable is worth looking at again. I'll attach a link for the adjustment procedure, as it explains it better than I could. Not saying you didn't do it right, but it should click and go through the self adjustment unless it's maximally tight, and perhaps something was missed. Is your fluid level good with a warm engine? If it's not the cable adjustment, which I hope solves it, I would look at the governor again. You mentioned the nylon gear as a possible culprit, but you didn't mention it in your examination of the governor. If not that, I may look into a servo issue or a valve body issue, but I think the former two are far more likely. If none of this has any positive affect, I would suspect the worst and consider that my forward sprag has gone out.
http://www.cpttransmission.com/tech_tvcable.htm

 

[74 Shortbed]

Not only does the adjustment needs to be right so does the geometry, no mention of what carb is being used??, (unless I missed that) it was predicated on the Q-Jet so if you have any other carb a proper throttle arm bracket is needed which is available from several sources, or fab one out yourself. But if the geometry isn't "right" it will not work no matter how the cable is adjusted..

 

[HotRodPC]

To eliminate the cable being the problem, disconnect it for a test run. DO NOT, repeat, DO NOT make quick take offs or use lots of throttle. Just take off with light throttle and gradually build your speed otherwise you'll fry your 3/4 clutch pack if not already fried.

Without the TV cable connected, you won't have an rise in fluid pressure to hold clutch packs tighter, but if it's not harmed otherwise, it should still shift through all the gears and it will shift very early and soft so listen close to see if it's shifting. If you're not even getting out of first gear and the governor is OK, then your 2/4 band is probably toast. If you're getting 1st and shift to 2nd but then acts likes its gone into N instead of shifting to 3rd, then the 3/4 clutch pack is toast.

 

[74 Shortbed]

I'd put it on jack stands for a test like that...

 

[Ashton84W]

Hmm... I think the TV cable is worth looking at again. I'll attach a link for the adjustment procedure, as it explains it better than I could. Not saying you didn't do it right, but it should click and go through the self adjustment unless it's maximally tight, and perhaps something was missed. Is your fluid level good with a warm engine? If it's not the cable adjustment, which I hope solves it, I would look at the governor again. You mentioned the nylon gear as a possible culprit, but you didn't mention it in your examination of the governor. If not that, I may look into a servo issue or a valve body issue, but I think the former two are far more likely. If none of this has any positive affect, I would suspect the worst and consider that my forward sprag has gone out.
http://www.cpttransmission.com/tech_tvcable.htm

So I've looked through everything for the TV Cable including you link which I thank you for. It's connected to the hook inside the tranny, no kinks as it is brand new and still no self adjustment. I ouch the "D" shaped button, moved the slider back against the bracket to the ratchet mechanism and manually pulled the throttle linkage on the carb. The cable simple slides through it's "sheath" and extends to its max which is very tight. No self adjustment. Like I said, it did the same thing on my other cable except it worked fine with the slider all the way back. The Governor Gear is not stripped. A little worm but no where near enough to cause any slipping. Can you do me a favor and explain what the servo does? Still new to this.

 

[Ashton84W]

Not only does the adjustment needs to be right so does the geometry, no mention of what carb is being used??, (unless I missed that) it was predicated on the Q-Jet so if you have any other carb a proper throttle arm bracket is needed which is available from several sources, or fab one out yourself. But if the geometry isn't "right" it will not work no matter how the cable is adjusted..

I have an Edelbrock 1406 Carb. I don't know about the bracket. Motor has been swapped and I can't get to the bolt on the bracket near the distributed. But the bracket worked with my other TV Cable. Everything worked fine until my water pump blew going down 278 and I had to limp home (slowly) I might add. That's when everything began acting funny.

 

[Ashton84W]

To eliminate the cable being the problem, disconnect it for a test run. DO NOT, repeat, DO NOT make quick take offs or use lots of throttle. Just take off with light throttle and gradually build your speed otherwise you'll fry your 3/4 clutch pack if not already fried.

Without the TV cable connected, you won't have an rise in fluid pressure to hold clutch packs tighter, but if it's not harmed otherwise, it should still shift through all the gears and it will shift very early and soft so listen close to see if it's shifting. If you're not even getting out of first gear and the governor is OK, then your 2/4 band is probably toast. If you're getting 1st and shift to 2nd but then acts likes its gone into N instead of shifting to 3rd, then the 3/4 clutch pack is toast.

That's kinda what is happening now. My truck is really REALLY LOUD and it's hard to hear anything over the straight pipes. When I manually shift from the colum and stuck it in first, once I reach bout 17mph the trans will slow the truck down as it should. With me in Drive/ OverDrive, I can reach the top speed of about 45mph before I back off and it doesn't jolt the truck into slowing down (if that makes any sense). Maybe it's shifting but if it is, I cannot feel it whatsoever! Cannot feel it nor hear it. It's really hard to feel/ hear with the way my truck is built.

 

[1987 GMC Jimmy]

Hmm... I'm guessing it maintains that tightness, which is good for the sake of your transmission. It's just weird that it doesn't act like it's supposed to when you attempt to adjust. You indicated that you can shift through the gears manually, yes, where it doesn't work unless you start in 1 and work your way up? That's why I suggested the forward sprag, but if I misunderstood you and that's not the case, I would consider other options, like those aforementioned. Did you get to try Hot Rod's suggestion with any success? Geometry is important. It should be straight and level from all perspectives and not jagged in any way. It's funny in a way that you started having issues on (I'm assuming) U.S. 278. I burnt up the original motor on my Jimmy the day I bought it while I was crossing 278 on I55 in Batesville, MS.

 

[HotRodPC]

So I've looked through everything for the TV Cable including you link which I thank you for. It's connected to the hook inside the tranny, no kinks as it is brand new and still no self adjustment. I ouch the "D" shaped button, moved the slider back against the bracket to the ratchet mechanism and manually pulled the throttle linkage on the carb. The cable simple slides through it's "sheath" and extends to its max which is very tight. No self adjustment. Like I said, it did the same thing on my other cable except it worked fine with the slider all the way back. The Governor Gear is not stripped. A little worm but no where near enough to cause any slipping. Can you do me a favor and explain what the servo does? Still new to this.

The Servo is what applies the 2/4 band when needed. One side of the band is connected to an anchor pin in the case, then the other side is pushed by the servo pin that tightens the band around the drum that it holds.

 

[74 Shortbed]

I have an Edelbrock 1406 Carb. I don't know about the bracket.

You need this on the throttle arm on the carb for proper geometry..

You must be registered for see images attach

 

[Ashton84W]

So just an update- decided to do a transmission pressure test. I couldn't find a tester to rent anywhere! AutoZone, Advanced, Walmart even. I wound up having a gauge with a 3/8 fitting on the end and just used that; stuck it right into the trans. Got my dad to shift gears while I took pics of the gauge reading- not easy with hot exauhat pipe in the way. No hosing means that I could drive and get reading and H.O.A. already hates me and how loud my truck is so I couldn't really rev. I don't know the proper pressure readings so if anyone does then that would help. Here's the readings...

Park :55-60
Reverse :85-90
Neutral :55-60
Over-Drive:55-60
Drive :55-60
2nd :85-90
1st :85-90

It jumped up in Reverse, 2nd and 1st and this was without any throttle. Got my Dad to pull the TV Cable and the readings just jumped around like crazy in Park. I couldn't tell at all. So my next step is to drop the pan. Really didn't want to but what can ya do? I was hoping it was just a stuck TV Valve but I don't know. If that was the case then I was gonna order a TransGo Shift Kit off EBay. Guess Im'a gonna have to see what the pan reveals tomorrow. Got a serious storm blowing through right now. So any suggestions as to what I should look for?

 

[74 Shortbed]

Here's a chart.

You must be registered for see images attach

 

[1987 GMC Jimmy]

You didn't change the filter, right? Maybe that's worth doing to see if you can get the pressure up before you do anything drastic. I forgot to do it on my Jimmy when I changed the fluid, and it was a night and day difference in how the transmission shifted after I went back and did it. I wonder about the torque converter and the pump, too, since they have a considerable affect on pressure...

 

[Ashton84W]

So yeah, my tranny fluid pressure is defiantly low by the looks of things. Decided to try and pull the Valve Body and boy does it look a bit daunting. Gotta think- I'm only 17 and this is slightly over my head. Took off all the connectors after carefully recording them and was just lost. I'm focusing right now on the TV Valve and it possibly sticking. Yes I know that if it was sticking them that would cause high pressure but doesn't hurt to look. Tried looking through YouTube and Google and whatnot and nothing is really to clear. Maybe I'm not looking hard enough? Anyone know of any good directions/pics of the removal? Any advice when it's out? Could really use some help here