Calling all 700R4 Experts!

[mister.freeze]

WELL, I’ve not refuted or argued anything, only shared my experiences and the results of all that has been done. It has in fact been rebuilt by different transmission shops as I’ve lived and moved around. The cabling and bracketry are the result of those ‘experts.’ Naturally, I want the simplest and least expensive solution. This is my daily driver and I have neither the time nor money to have another shop just do what others have done before. Nobody, yet, understandably, has committed to one solution or other, like the governor or TV.

Regarding the cable: i took it off thinking it was binding inside or otherwise worn out. The new one I bought was wrong. The old one moved freely and was not otherwise compromised. So I reinstalled it. It was kind difficult, resulting in me repeatedly tugging on the end inside the transmission to hook it to the cable. The next day is when 4th gear reappeared. It has since gone away, despite the geometry-correcting bracket still being on there. That means the bracket didn’t change anything.

Fancy switch is for the converter lockup. That has never been an issue.

[simicrintz]

Like I said, not trying to be a jerk but rather making an observation(s). I see replies like this "That’s all well and good, but I’v Had this setup for years, as described above" which is fine, but just because it's been that way for years doesn't make it right (seems this never worked right, so that would back this observation). Post #14 on page 1 seems like a great starting point; did that ever get put in play?

I'd like to see you get this fixed and after 4 pages of posts it seems like you are no closer than you were on page 1.

[mister.freeze]

Because I can do it simply, checking the gov is next on the to-do list.

Today, I backed off some tension on the TV cable and guess what: 4th gear is back, though it shifts earlier than I would like. Looks like I need more travel: less tension at near-idle and full tension at WOT. The geometry corrector linkage is not doing the trick. I’ll fab a longer one.

[jjzepplin]

I don't think you heard the last post. Forget what you "think" and listen to and respond to proven results from guys and gals that have been there and done that. Your trans might not be responding to fixes because it is malfunctioning internally. The bracket may not have changed much but will be necessary if you ever want this trans to work correctly. I cannot believe that hundreds of us have the right bracket and our trans work fine but you are the only one with issues. We all want to see you drive your truck and have it function correctly. It seems as if you are the only one that doesn't. You could just keep throwing screwdrivers at it OR you could do as others have suggested. Trying your own methods with questionable results are why you are here. I know this is frustrating but hang in there.

[mister.freeze]

alright then. What gauge do I need, and where do I connect it? What readings should I have and when?

Obviously, something is not right, and hasn't been for some time. However, the symptoms I'm experiencing I've not had in the past. The corrector bracket doesn't seem to have worked because the symptoms returned. The work of previous re-builders would seem to have fixed those problems (losing 2 and 4), yes? I do what I can with the time and resources I have. If those weren't so limiting, we wouldn't be here. Also, I believe a 700r4 is a common transmission for these trucks, and a thorough discussion of symptoms, treatments, and, hopefully cures, will benefit more than just me.

[made2drag]

Originally Posted by mister.freeze

No actual changes. Still no 4th gear.
While I agree, proper geometry is ideal, this has worked FOR YEARS as is. I'm trying to find out A) what causes a loss of just 4th gear and B) if it's something I can live with given my driving habits or do I need to start investing in a new transmission?
Might anybody know if there's an Allison that is a direct replacement for the 700R4?

Ok, I know this is an old post and you recently got 4th back.

Things to check:

Have someone hold your gas pedal down all the way to the floor (not running) and feel how tight the TV cable is. If it's like almost as tight as a guitar string, it should be good.

While driving watch your speed around 50-55 and see if you see any rpm drops and if not, move from OD to D....do this like 10 times and you may see it shift. If it starts working it will probably keep working like mine did. Also, make sure your fluid is showing at the top of the operation mark on the dipstick, if it's even a hair lower than the crosshatching it may not ever shift into 4th. Check it after 30 mins of driving to make sure you get a good solid reading and if you add some, drive another 10 mins and check again.

A th350 low on fluid will not drive at all, a 700r4 will drive fine in 1,2,3.

Also, mine still wasn't shifting to 4th even with it hot after a 30 mins drive and showing on the full mark, until I did the OD to D shifts back and forth. I drove like 10 mins shifting it back and forth and it finally felt a shift.

I have 3.08 gears and a 26" tire and mine shifts at 17, 30 and 52 MPH.

Another rabbit to run is to make sure your dipstick is a stock 700r4 dipstick. I had a aftermarket dipstick in my last truck that gave me false readings for full. Not sure why people stick those Lokar dipsticks in....Junk.

[SeventyOne]

Originally Posted by mister.freeze

I’m starting to think that the geometry is still wrong: a longer arm on the carb would mean more travel on the TV cable. I kinda feel it’s too tight at idle, but not being pulled enough for proprt shifting

You think? I've said that from the start. Get the bowtie overdrive kit and be done with this already.

[made2drag]

Originally Posted by SeventyOne

You think? I've said that from the start. Get the bowtie overdrive kit and be done with this already.

LOL, dude take a chill pill.

[SeventyOne]

Originally Posted by made2drag

LOL, dude take a chill pill.

I'm chill. I just find it frustrating when people ask for advice then ignore it and complain the problem isn't fixed. Basically =

[SeventyOne]

Thinking more on this and I want to be helpful so - some things I want to add/restate:

Yes you got the geometry corrector for the carb throttle. Good - but if you don't have the correct carb base plate bracket where the TV cable and throttle attach the geometry is still going to be wrong.

For the TV cable to work properly its about length of pull and tension - see post 41. If you don't have those angles correct it is not going to operate correctly. I don't know how you get those numbers by using parts that are not made for the correct application. Sure you can fab it up but those are the number you need. Or just buy the bowtie OD setup i referenced and also shown on post 8. Please note that the cable is supposed to be TIGHT.

Since you asked for the pressure test readings please see here:

http://67-72chevytrucks.com/vboard/s...d.php?t=169445

[made2drag]

Originally Posted by SeventyOne

I'm chill. I just find it frustrating when people ask for advice then ignore it and complain the problem isn't fixed. Basically =

I get it. Hopefully he gets the TV cable bracket sorted and it fixes it. Transmissions, especially 700's are irritating to troubleshoot. Everyone has an opinion, but it really helps to see whats going on in person. It could be a combination of things going on.

[made2drag]

Originally Posted by SeventyOne

Thinking more on this and I want to be helpful so - some things I want to add/restate:

Yes you got the geometry corrector for the carb throttle. Good - but if you don't have the correct carb base plate bracket where the TV cable and throttle attach the geometry is still going to be wrong.

For the TV cable to work properly its about length of pull and tension - see post 41. If you don't have those angles correct it is not going to operate correctly. I don't know how you get those numbers by using parts that are not made for the correct application. Sure you can fab it up but those are the number you need. Or just buy the bowtie OD setup i referenced and also shown on post 8. Please note that the cable is supposed to be TIGHT.

Since you asked for the pressure test readings please see here:

http://67-72chevytrucks.com/vboard/s...d.php?t=169445

I agree

[made2drag]

https://www.youtube.com/watch?v=D109Fz1SK18

Good video on adjustment. Start at 8:42

[SeventyOne]

Also EVEN if you get the geometry nailed by installing the correct parts...YES you could have other ailments like the sticking, etc.

That said I have to think the TV cable is the issue. You have a low mile rebuild essentially on your hands. But if its easy/cheap to check/diagnose the governor and a sticking throttle valve then by all means do that in addition. But first you have to get the parts to make it operate correctly first and foremost. Otherwise its like...lipstick on a pig? Polishing a turd? I dunno...pick your idiom.

Good luck Mister Freeze.

[kwmech]

Wow, this is still going on? I gave up 2 weeks ago.

I think there is going to be an internal problem after all this time. In my experience the 700s are not too forgiving after being set-up wrong for so long.

[YoungPup1977]

Simple

GOOD LUCK MR FEEZE !!!

[mister.freeze]

Regarding the TV cable: The end that goes into the trans is BIGGER than the supposed replacement cable. It also does not have the button for adjustment. The part that locks into the carb base plate bracket is threaded- it must be removed from the bracket and screwed in or out to adjust the cable sleeve. That's probably why it has the brass thing on the end to adjust the tension. As stated before, this cable moves freely and is otherwise in good shape.

[mister.freeze]

Originally Posted by SeventyOne

Thinking more on this and I want to be helpful so - some things I want to add/restate:

Yes you got the geometry corrector for the carb throttle. Good - but if you don't have the correct carb base plate bracket where the TV cable and throttle attach the geometry is still going to be wrong.

For the TV cable to work properly its about length of pull and tension - see post 41. If you don't have those angles correct it is not going to operate correctly. I don't know how you get those numbers by using parts that are not made for the correct application. Sure you can fab it up but those are the number you need. Or just buy the bowtie OD setup i referenced and also shown on post 8. Please note that the cable is supposed to be TIGHT.

Since you asked for the pressure test readings please see here:

http://67-72chevytrucks.com/vboard/s...d.php?t=169445

So... what gauge and where to plug it in? I don't have a gauge, but I could get one. I don't have the typical port for the lockup pressure switch, so where else could it go?

[mister.freeze]

Originally Posted by made2drag

Ok, I know this is an old post and you recently got 4th back.

Things to check:

Have someone hold your gas pedal down all the way to the floor (not running) and feel how tight the TV cable is. If it's like almost as tight as a guitar string, it should be good.

While driving watch your speed around 50-55 and see if you see any rpm drops and if not, move from OD to D....do this like 10 times and you may see it shift. If it starts working it will probably keep working like mine did. Also, make sure your fluid is showing at the top of the operation mark on the dipstick, if it's even a hair lower than the crosshatching it may not ever shift into 4th. Check it after 30 mins of driving to make sure you get a good solid reading and if you add some, drive another 10 mins and check again.

A th350 low on fluid will not drive at all, a 700r4 will drive fine in 1,2,3.

Also, mine still wasn't shifting to 4th even with it hot after a 30 mins drive and showing on the full mark, until I did the OD to D shifts back and forth. I drove like 10 mins shifting it back and forth and it finally felt a shift.

I have 3.08 gears and a 26" tire and mine shifts at 17, 30 and 52 MPH.

Another rabbit to run is to make sure your dipstick is a stock 700r4 dipstick. I had a aftermarket dipstick in my last truck that gave me false readings for full. Not sure why people stick those Lokar dipsticks in....Junk.

YES!!! Practical experience!
The shifting in and out of 4 (OD) supports the sticky valve idea.
I currently shift at 16, 24. haven't driven enough to find a consistent upshift speed into 4th.
fluid level is correct.

[SeventyOne]

Originally Posted by mister.freeze

So... what gauge and where to plug it in? I don't have a gauge, but I could get one. I don't have the typical port for the lockup pressure switch, so where else could it go?

Do you have a search function? It's pretty useful. Google is your friend.

http://67-72chevytrucks.com/vboard/s...d.php?t=526152

https://www.youtube.com/watch?v=Av6Xh8Fwuy0

https://www.amazon.com/Advanced-ATD-.../dp/B000OUZBZ0

https://www.cargurus.com/Cars/Discus...27790_ds705889

What you said above about your TV cable...makes it sound like its the wrong cable.

http://www.monstertransmission.com/7...ons_ep_62.html

[made2drag]

Originally Posted by mister.freeze

YES!!! Practical experience!
The shifting in and out of 4 (OD) supports the sticky valve idea.
I currently shift at 16, 24. haven't driven enough to find a consistent upshift speed into 4th.
fluid level is correct.

If you have big tires your actual speed will be slower on your guage, which is good, because all my reading says 1st to 2nd should happen between 17-20 and sooner shifts is bad for trans. Sounds like you might actually be shifting closer to 20 into 2nd and 30 into 3rd. Im using a gps unit that just plugs into my cig lighter to check my speeds.

I keep reading that after a rebuild 4th acts up but eventually works again. I know yours was working and recently quit so I don't know if that applies... I know lots of people wont believe it but that's what I keep reading. The other thing I read was driving til it shifts to 2nd then turn key off, then crank back up in neutral, then shift into OD again. Something about fluid movement but I cant remember now.

[jjzepplin]

Originally Posted by SeventyOne

Do you have a search function? It's pretty useful. Google is your friend.

http://67-72chevytrucks.com/vboard/s...d.php?t=526152

https://www.youtube.com/watch?v=Av6Xh8Fwuy0

https://www.amazon.com/Advanced-ATD-.../dp/B000OUZBZ0

https://www.cargurus.com/Cars/Discus...27790_ds705889

What you said above about your TV cable...makes it sound like its the wrong cable.

http://www.monstertransmission.com/7...ons_ep_62.html

Easy tiger. I know how to use the search function but it's so much more fun to have you do it for us. HAHA! That is some good info. Would have been nice to have before this trans went bonkers. I have a nice video (tape) yup on how to rebuild these. I might just put it on a drive and send it to you. Not hard at all.

[mister.freeze]

this is the cable I have, as far as the ends go. I did not measure the length when I had it out.
https://www.transmissioncenter.com/s...3254l-teckpak/

[YoungPup1977]

Qq.....

[mister.freeze]

Originally Posted by YoungPup1977

Raise the rear wheels off the ground and make sure Transfer case is in 2H and run it thru the gears just like made2drag indicated.....do you have a tach on your daily truck ?

this way you have no excuse for only going 45 MPH and not getting it into 4th and lockup if they even work.....

shift the hell out of the thing manually and see where that takes ya.....

maybe it might fix itself like made2drag said happened to his....4th comes back ??

What was wrong with the new TV cable ? you said it was wrong, what was wrong about it....when you replace the cable unhook it from the carb and bracket before you disconnect it from the trans.....at the trans once disconnected from carb and bracket remove the 10 mm bolt and pull up on the cable and disconnect the cable once you pull up on the cable exposing the small metal rod from inside the pan....slides out of the cable end..... easy stuff....even I can do it.

Your old cable could be binding, so you already spent money on new cable...go exchange it if its wrong get the right one...you want me to call the parts place you bought the cable from and make sure you get the right one ??

We want this fixed today, this is your daily right ? Hate to see young guys struggle....you are a young guy correct ?

Wow. Well... for starters, the short piece of shroud that actuallu goes in to the transmission is bigger than the “correct” cable, meaning the hile is bigger and the cable won’t seal.

No, no tach.

Young feller? Not if you’re asking me. I’ve had this truck for 20 years...

After all the debate and the results of different things that have been suggested and tried, the proper WOT doesn’t release the cable enough at idle or near idle. I believe this is called the preload tension.

Obviously, this is some sort of frankenstein transmission despite ‘professionals’ having worked onbit before. The lack of the correct side port and the TV cable hole size both point to this.