Trans. shift point Q.
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Basically you're saying it never uses 3rd gear, it just drops into overdrive instantly.
Does it come out if you get on it, or just bog? How about the other gears, do they shift too easy under heavy throttle and cause it to bog?
I have this problem on a 700R4 also, but only with 3rd gear where it dumps into overdrive instantly and bogs and won't come out easy under power. TV cable feels excellent in every other gear.
Does it come out if you get on it, or just bog? How about the other gears, do they shift too easy under heavy throttle and cause it to bog?
I have this problem on a 700R4 also, but only with 3rd gear where it dumps into overdrive instantly and bogs and won't come out easy under power. TV cable feels excellent in every other gear.
Race Director
Joined: Jun 2004
Posts: 13,943
Likes: 705
From: WI
The TV cable adjusts fine? Mine was worn out and would adjust fully extended. Maybe Pete will chime in on this one. You could try throwing a shift kit at it. There would be new springs and get one with a seperator plate. The seperator plate on mine was very worn around the two check *****. I also had trouble with very delayed shifting into OD, there was hard plastic varnish in the valve body.
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Thread Starter
Racer
Joined: Sep 2006
Posts: 446
Likes: 1
From: Punta Gorda Florida
I hadn't driven the car in a while, and had a problem with it leaking while sitting. I finally got it out and took it for a nice cruise around the neighbor hood. It has all of it's gears just to shift out of second requires the RPM's to be around 2500 before it will even think about shifting. I'm not sure that's a normal operation? I'll do a shift kit someday if I need to, but not til then.
Under heavy throttle it seemed to shift fine. I'm just curious at to what RPM's is a typical shift out of 2nd with light throttle useage? (I do not have a visible speedo)
TV cable adjustment? Someone want to explain when this is needed and how to perform..
Under heavy throttle it seemed to shift fine. I'm just curious at to what RPM's is a typical shift out of 2nd with light throttle useage? (I do not have a visible speedo)
TV cable adjustment? Someone want to explain when this is needed and how to perform..
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
My '88 FSM lists differing shift points for different models of 700R/4:
For FAM, FMM, MAM min throttle up-shift speeds are:
1-2 = 12-15mph (1300-1600rpm)
2-3 = 19-26mph (1200-1500rpm)
3-4 = 41-51mph (1500-1800rpm)
1-2 = 31-43mph (3400-4700rpm)
Note: rpm at stated mph based on 2.59 gears.
For FAM, FMM, MAM min throttle up-shift speeds are:
1-2 = 12-15mph (1300-1600rpm)
2-3 = 19-26mph (1200-1500rpm)
3-4 = 41-51mph (1500-1800rpm)
1-2 = 31-43mph (3400-4700rpm)
Note: rpm at stated mph based on 2.59 gears.
Safety Car
Joined: May 1999
Posts: 3,651
Likes: 5
From: Atlantis
Cruise-In I Veteran
Wahhhhhhhh. Meeehhhhhhh.
There's a thingy'ma'bob on the side of the transmission that's called the 'governor'.
The 'governator' if you're in Cali.
It has some little weighty thingy'jigs sort of like the centrifugal weights in the distributor of your older car.
The governor controls the shift points.
I'm not too sure the shift points are RPM controlled......
At least not in the 700R4. They are 'SPEED' controlled..... the governor 'senses' the rotational speed of the output shaft. It's a little hard to DEFINE THE RPM since the crankshaft is NOT directly connected to the TAILSHAFT until the TORQUE CONVERTER locks up.
That fluid coupling makes the RPM calculation pretty imprecise.
I don't know 'bout the 4L60E....
Which one we talking about?
PeteK knows ALL this stuff. Let's ask HIM!!!!
There's a thingy'ma'bob on the side of the transmission that's called the 'governor'.
The 'governator' if you're in Cali.
It has some little weighty thingy'jigs sort of like the centrifugal weights in the distributor of your older car.
The governor controls the shift points.
I'm not too sure the shift points are RPM controlled......
At least not in the 700R4. They are 'SPEED' controlled..... the governor 'senses' the rotational speed of the output shaft. It's a little hard to DEFINE THE RPM since the crankshaft is NOT directly connected to the TAILSHAFT until the TORQUE CONVERTER locks up.
That fluid coupling makes the RPM calculation pretty imprecise.
I don't know 'bout the 4L60E....
Which one we talking about?
PeteK knows ALL this stuff. Let's ask HIM!!!!
Last edited by VetNutJim; Mar 23, 2007 at 11:53 PM.
Safety Car
Joined: May 1999
Posts: 3,651
Likes: 5
From: Atlantis
Cruise-In I Veteran
Sounds like the throttle VALVE is stuck in the tranny.
There was a mod that placed an extra spring behind it to keep the valve from sticking.
It's a pretty minor thing to fix even if you have to pull the pan.
The throttle valve controls the transmission 'Line Pressure'. They usually stick in the 'High Pressure' position.
It will shift but it will shift HARD and at a much higher SPEED than normal.
You 'MAY' get it unstuck by some heavy footed driving and several cycles of heating it up and cooling it down.
You'll be giving it 'HELLO' if you decide to try this method. Sometimes it works and sometimes it doesn't.
Adjusting the TV Cable isn't going to fix it , HOWEVER....
You 'MAY' want to disconnect the TV cable from the throttle body and vigorously move it in and out.... THis 'may' shock the valve back into position.
After you do that.... ADJUST IT BACK AS DESCRIBED IN THE FSM....
Don't 'Experiment' around with it. Adjust it correctly and leave it alone after you get the problem squared away.
This seems to be a semi-common thing with these transmissions.
PeteK..... HE"S DA 'Transmission Main Man'!!!!
Last edited by VetNutJim; Mar 24, 2007 at 12:00 AM.
Safety Car
Joined: May 1999
Posts: 3,651
Likes: 5
From: Atlantis
Cruise-In I Veteran
Don't worry about the 3 to 4 back to back upshift.
The reason it's doing this is because it's accelerating to the 3rd gear shift point because you have to 'nail it' to get'er to shift from 2nd to 3rd.
When it does, you probably let off the gas and then it's ready to shift to 4th.
If it's a stuck THROTTLE VALVE all these problems will be fixed with one remedy.
You DON"T need a shift kit to fix this. It's ALREADY acting kind of like it's GOT one. LOL,LOL.
No offense meant to anybody.
The reason it's doing this is because it's accelerating to the 3rd gear shift point because you have to 'nail it' to get'er to shift from 2nd to 3rd.
When it does, you probably let off the gas and then it's ready to shift to 4th.
If it's a stuck THROTTLE VALVE all these problems will be fixed with one remedy.
You DON"T need a shift kit to fix this. It's ALREADY acting kind of like it's GOT one. LOL,LOL.
No offense meant to anybody.
Thread Starter
Racer
Joined: Sep 2006
Posts: 446
Likes: 1
From: Punta Gorda Florida
until pete k chimes in, the assumption (even tho assumptions are not always right in most cases) is that it could likely be a stuck throttle valve? Would a transmission additive help in releasing it into normal operation? I plan on having ALL fluids changed when It's ready for the road again.
Race Director
Joined: Feb 2004
Posts: 12,517
Likes: 19
Start with making SURE the transmission is FULL of fluid. Not OVER FILLED and not UNDER FILLED.
Sounds like the throttle VALVE is stuck in the tranny.
There was a mod that placed an extra spring behind it to keep the valve from sticking.
It's a pretty minor thing to fix even if you have to pull the pan.
The throttle valve controls the transmission 'Line Pressure'. They usually stick in the 'High Pressure' position.
It will shift but it will shift HARD and at a much higher SPEED than normal.
You 'MAY' get it unstuck by some heavy footed driving and several cycles of heating it up and cooling it down.
You'll be giving it 'HELLO' if you decide to try this method. Sometimes it works and sometimes it doesn't.
Adjusting the TV Cable isn't going to fix it , HOWEVER....
You 'MAY' want to disconnect the TV cable from the throttle body and vigorously move it in and out.... THis 'may' shock the valve back into position.
After you do that.... ADJUST IT BACK AS DESCRIBED IN THE FSM....
Don't 'Experiment' around with it. Adjust it correctly and leave it alone after you get the problem squared away.
This seems to be a semi-common thing with these transmissions.
PeteK..... HE"S DA 'Transmission Main Man'!!!!
Sounds like the throttle VALVE is stuck in the tranny.
There was a mod that placed an extra spring behind it to keep the valve from sticking.
It's a pretty minor thing to fix even if you have to pull the pan.
The throttle valve controls the transmission 'Line Pressure'. They usually stick in the 'High Pressure' position.
It will shift but it will shift HARD and at a much higher SPEED than normal.
You 'MAY' get it unstuck by some heavy footed driving and several cycles of heating it up and cooling it down.
You'll be giving it 'HELLO' if you decide to try this method. Sometimes it works and sometimes it doesn't.
Adjusting the TV Cable isn't going to fix it , HOWEVER....
You 'MAY' want to disconnect the TV cable from the throttle body and vigorously move it in and out.... THis 'may' shock the valve back into position.
After you do that.... ADJUST IT BACK AS DESCRIBED IN THE FSM....
Don't 'Experiment' around with it. Adjust it correctly and leave it alone after you get the problem squared away.
This seems to be a semi-common thing with these transmissions.
PeteK..... HE"S DA 'Transmission Main Man'!!!!
Jim is 100% dead on.
Race Director
Joined: Feb 2004
Posts: 12,517
Likes: 19
Avoid additives at all costs. They are primarily designed to soften and swell the rubber lip seals in the trans. They work well in that regard. The problem is that most think if 1 can is good, 2 or 3 or 4 are even better.
This causes the seals to turn to goo and ruins the trans.
As a last resort, after doing evryevthing you can to solve the problem, 1 can of liquid magic is all you need.
This causes the seals to turn to goo and ruins the trans.
As a last resort, after doing evryevthing you can to solve the problem, 1 can of liquid magic is all you need.