Thread: 700-R4--> Shifting inconsistently

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Last night when I took my car out for a drive, it started downshifting form 4th gear to 3rd early, and not shiftintg to 4th.

I took it on the road for 30 miles this morning, and it did fine on the freeway, but when I stopped at a toll booth, it didn't want to shift out of 1st.

Bringing it back home, I found it didn't want to downshift to 1st when stopping, unless I did it manually. And it was reluctant to upshift to other gears. If I manually dropped it to the lower gear, and back up to the higher gear manually, after 3-4 attempts, it would shift.

My transmission cooler has a fan on it, with a temp control. I have a pilot light tha tlights when the fan comes on. It appeared to me that it wasn't coming on but very little, although it would come on some, but not for long. It is a cool morning, and I know that when it's cool, that has seemed normal. Although, with this going on, I paid a lot of more attention to it, and it seems like it wasn't on as much as it should be. I had heared that a 700-R4 did not have a fluid pump, and that it only pumped fluid when in 4th gear. Most of the time I was not in 4th gear (didn't much want to go into that gear). Although, I know that very commonly the fan does come on on the cooler when driving around town.

I changed the fluid a few weeks ago, and it looked good, and not full of metal shavings.

Anhy ideas what would cause this type of problem?

Could it be too much fluid? (I have a braided transmission dip stick line, and a plastic dip stick. Fluid doesn't want to stick to the stick, and I wonder if it is running down the stick when I check it, making it look ok on level when it is actually too full.)

Any thoughts appreciated.

Originally posted by ewingr
Last night when I took my car out for a drive, it started downshifting form 4th gear to 3rd early, and not shiftintg to 4th.

I took it on the road for 30 miles this morning, and it did fine on the freeway, but when I stopped at a toll booth, it didn't want to shift out of 1st.

Bringing it back home, I found it didn't want to downshift to 1st when stopping, unless I did it manually. And it was reluctant to upshift to other gears. If I manually dropped it to the lower gear, and back up to the higher gear manually, after 3-4 attempts, it would shift.

My transmission cooler has a fan on it, with a temp control. I have a pilot light tha tlights when the fan comes on. It appeared to me that it wasn't coming on but very little, although it would come on some, but not for long. It is a cool morning, and I know that when it's cool, that has seemed normal. Although, with this going on, I paid a lot of more attention to it, and it seems like it wasn't on as much as it should be. I had heared that a 700-R4 did not have a fluid pump, and that it only pumped fluid when in 4th gear. Most of the time I was not in 4th gear (didn't much want to go into that gear). Although, I know that very commonly the fan does come on on the cooler when driving around town.

I changed the fluid a few weeks ago, and it looked good, and not full of metal shavings.

Anhy ideas what would cause this type of problem?

Could it be too much fluid? (I have a braided transmission dip stick line, and a plastic dip stick. Fluid doesn't want to stick to the stick, and I wonder if it is running down the stick when I check it, making it look ok on level when it is actually too full.)

Any thoughts appreciated.

had heared that a 700-R4 did not have a fluid pump, and that it only pumped fluid when in 4th gear.
not true, 700-r4 work just like all the rest

most of the time to much fluid "will not" effect the shifting of a trans. if its to much in it, it will blow it out of the breather.

"not enough" fluid will cause the problem.

sounds like the fan is doing what its suppose to.

get someone to check your shift cable adj. if thats ok sounds like youve got some internal troblems.

Now that I think about it more, when I had this tranny built, the shop told me to be sure to have power to the thing on the side (don't know what it's called) that allows it to shift into 4th gear. When no power, it doesn't shift into 4th. And he told me it was very important I do have that hooked up, as the transmission would overheat if driving over 55 without that. I thought he said it didn't have a pump. But it was most likely a misunderstanding.

Since posting a bit ago, it has cooled of some, and I went out and looked at the tranny fluid. It is obviously darker. I am pretty sure it has something to do with overheating. The fluid even smells off.

So, bad pump sound like a likely option? Do you know if that can be replaced w/o having to pull the transmission?

[edit]
Regarding the cable adj: Last year I put on a 'kit' from Bowtie Transmissions for this trans. I checked settings/pressures, and conferred with them and got validation of that. I don't think that is it, but who knows.l

Originally posted by ewingr
Now that I think about it more, when I had this tranny built, the shop told me to be sure to have power to the thing on the side (don't know what it's called) that allows it to shift into 4th gear. When no power, it doesn't shift into 4th. And he told me it was very important I do have that hooked up, as the transmission would overheat if driving over 55 without that. I thought he said it didn't have a pump. But it was most likely a misunderstanding.

Since posting a bit ago, it has cooled of some, and I went out and looked at the tranny fluid. It is obviously darker. I am pretty sure it has something to do with overheating. The fluid even smells off.

So, bad pump sound like a likely option? Do you know if that can be replaced w/o having to pull the transmission?

[edit]
Regarding the cable adj: Last year I put on a 'kit' from Bowtie Transmissions for this trans. I checked settings/pressures, and conferred with them and got validation of that. I don't think that is it, but who knows.l

sounds like you might not have your torque converter lock-up kit installed properly. if its not you may have a torque converter gone bad. make sure you have the sw. wired right. i think what you need most is a trans. man. thats some of the weak points to the 700-r4's trans. shift cable and conv. lock up.

Yeah, at this point I'm sure I need a trans man

I'm just curious now if I'm going to have to actually pull the trans to fix it. It's in the convertible, and I doubt it will come out w/o pulling the engine. Major PIA.

I've been driving this since 1999, althought it only has 13,000 miles on the build.

For sure, the fluid is burnt. Just not sure what would cause that. It seems obvious that it is not pumping through the cooler, as the fan is not coming on enough (temp unit on cooler that turns fan on.)

I'll be calling the transmission shop on Monday.

A 700/R4 will burn up in very short order if the lockup is not correctly wired.

Well, I just checked the switch on the side of the tranny, and the hot wire is hot, when engine is on.

The other wire...I don't know where it leads to. The transmission guy wired it, and it is soldered.

I wonder if that switch could be bad.

Originally posted by ewingr
Well, I just checked the switch on the side of the tranny, and the hot wire is hot, when engine is on.

The other wire...I don't know where it leads to. The transmission guy wired it, and it is soldered.

I wonder if that switch could be bad.

where is your cooler at? if its so air will flow across it going down the road then the fan wouldnt come on untill you stopped or slowed down. i bet the fan is ok.

that lock-up has to work or you gonna keep having trans. problems.

Originally posted by lt1s10
where is your cooler at? if its so air will flow across it going down the road then the fan wouldnt come on untill you stopped or slowed down. i bet the fan is ok.

that lock-up has to work or you gonna keep having trans. problems.

The cooler is under the floorboard. Not what I would call real direct air flow, that is why I got one with a fan.

I'm not sure how to tell if the lockup is working. It has power, and has been wired this way for 13000 miles.

Maybe there is a way to test the switch.

Sounds like you folks are thinking it is related to the lockup, as opposed to a bad pump.

Could something other than a bad switch cause the lockup failure? (I am presuming that it would have failed much sooner than this if it were 'wired wrong'. Although only 13000 miles on this trans, that includes a couple 2500 mile round trips to Mississippi Cruisin' the Coast runs).

Originally posted by ewingr
The cooler is under the floorboard. Not what I would call real direct air flow, that is why I got one with a fan.

I'm not sure how to tell if the lockup is working. It has power, and has been wired this way for 13000 miles.

Maybe there is a way to test the switch.

Sounds like you folks are thinking it is related to the lockup, as opposed to a bad pump.

Could something other than a bad switch cause the lockup failure? (I am presuming that it would have failed much sooner than this if it were 'wired wrong'. Although only 13000 miles on this trans, that includes a couple 2500 mile round trips to Mississippi Cruisin' the Coast runs).

it hard to say what it is but, trans. front pumps dont give much trouble anymore. the conv. with the lock-up is more of a problem. you want know untill you check it. it could be the lock-up sol. in the trans. and not the conv. but i cant tell you how to check it here. you need a trans. man.

you tv valve is sticking in the valve body this is the mosy sensitve part of a 700 r4 I almost never see one that is sticking that you can kleen or replace and fix the problem the trans is coming apart and metal has cause the valve to stick the reason you need the converter to lock-up is that Gm put a orifice in the 4th gear curcuit be cause 99% of the time your in 4th the converter will be locked up when it locked up it makes no heat gm wants it to run at 200 to 280 degrees.when the converter is not locked up it make 99% of all the heat in the trans . you need a trans

Yep!

Turns out the torque converter shot craps!

Been rebuilt now and working fine.

Argh...

Good to know man. Thanks for comming back and letting us know what happened. Most guys post their question and just leave. I was following this thread when you first posted it and wanted to find out what it was. Totally forgot about it but remember this thread clearly now.