700r4 help

catfishblues

catfishblues

Well-Known Member
Joined
Jul 26, 2005
Location
Pfafftown, NC
Tranny in the 87 Suburban started acting up today. It was sticking in gear like I was flooring it the whole time. Basically holding each gear until redline regardless of throttle input, and shifting very hard, unless it was actually floored. Then it shifted smooth. It would also downshift fairly violently if I got below a certain speed threshold. I don't think it was even getting into OD. It did this for about 10-12 miles, with a couple of stops, then seemed to clear up right before I got home. I took it once around my test road to see what it did, and it wouldn't act up again.

Now there's a lot of miles on this tranny. It's been at least 130-150k since it was rebuilt. It was my dad's before I got it, so I know the history. It was treated well, but it did tow a 22' sailboat occasionally. I haven't towed much with it since I got it, and I baby it when I do tow. The fluid is full, but it's brown. It has been for about 7 years now. It went brown on my dad, and he and I have both been told by trans guys that it's better to leave in the brown than change it at this point.

Am I dead, or is there still hope? Any help would be appreciated. I hate autos!
 
Try adjusting the TB cable by your Throttle Body. Turn your truck off and push the little button in on the side, hold and push the cable back in the housing. do not take the cable off your throttle body. Then get inside the truck and stomp on the gas one good time. You should hear it clicking as you do it. Then take it out and try it.
 
Better to leave it brown? I have NEVER heard that...

The trans in my Dodge would start to shift funny when the fluid got old.
 
Rich said:
Better to leave it brown? I have NEVER heard that...
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x2

I would check the TV cable, if these come loose (or break) they will do all kinds of funny shifts.

My recommendation would be to drop the pan, check the TV cable while your in there replace the filter, and refill.

Honestly 150k on a 700 with some towing thrown in and no after market cooler or anything is getting near the end. But thats not to say you couldnt eek out another 15 to 20k with some fresh fluid.
 
SkyHiK5 said:
x2
I would check the TV cable, if these come loose (or break) they will do all kinds of funny shifts.
My recommendation would be to drop the pan, check the TV cable while your in there replace the filter, and refill.
Honestly 150k on a 700 with some towing thrown in and no after market cooler or anything is getting near the end. But thats not to say you couldnt eek out another 15 to 20k with some fresh fluid.
Click to expand...

Forgot to mention, it's the factory tow package with the big front-mounted trans cooler. The explanations I've heard about the fluid range from it needing to be power flushed, and the guy not having the equipment, to "Once it's brown, the particles in the fluid help hold things together. Change it and it'll go shortly thereafter." Allow me to reiterate, I hate automatic transmissions! The 700 is fine while it's working. I like the gearing of it. If I had my druthers, though, I'd slap an NV4500 in and be done with it, but that'd be an expensive pain in the ass.
 
If the TV cable is broken then the transmission is already blown. The tv cable is the most important input to a 700, drive it around the block with it off and the whole trans is junk

There are pretty specific guidelines to follow when adjusting the TV, let me try to find the article and i'll post it. But more than likely you'll need a rebuild.

My rebuilt 700's have no problems going another 200k. They work better then they did from the factory
 
I would recommend changing the filter and fluid along with checking the TV cable. When I bought my 700r4 from Bowtie Overdrives the things they stressed to me were to run a big tranny cooler, change the fluid and filter at least once a year, and they were really big on making sure the TV was properly adjusted.

I don't see why it would be bad to change the fluid just because its been in there that long. Would you not change the oil in your engine just because its been in too long? Maybe there is something I don't know.
 
AV8 said:
I would recommend changing the filter and fluid along with checking the TV cable. When I bought my 700r4 from Bowtie Overdrives the things they stressed to me were to run a big tranny cooler, change the fluid and filter at least once a year, and they were really big on making sure the TV was properly adjusted.
I don't see why it would be bad to change the fluid just because its been in there that long. Would you not change the oil in your engine just because its been in too long? Maybe there is something I don't know.
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You know more than I do, I promise that. The info I've gotten has been from people who were supposed to know more than me. I am by no means a novice, but I know my limits. I don't claim to know a thing about an auto transmission. I'd like to learn them someday, but for now, they work by magic as far as I know. I'll change the fluid and check the cable as soon as I can. I feel like crap right now, though, and getting out in the cold to work is not high on my priority list. If anybody's got any more ideas, though, I'm still listening. I've got several good things to check. Thanks, guys! I owe you one. :beer:
 
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