ot2bnla

Hi all,

Not sure if anyone here can help or not but this is my situation. Three days ago cel comes on, I get it checked out and it's a p0700 code. Reset the codes to see if it would come back on. Start the truck up yesterday and the light comes back on, go to reverse and the truck felt like it didn't want to engage but a second try and it goes. Today I go to work and I'm getting high revs in second and third, doesn't kick into fourth. I bring the truck to the dealership to have them scan it, P0700 and p0740. Guy says we have to drop your transmission most likely it will be a broken valve in there it will take a few days. I say I'll have a friend of mine check it out he works at a transmission shop. The guy grabs my keys off the table and seems very irritated. I go pay the bill for the diagnosis and about 10 mins later my truck gets parked out front. I jump on the internet to check for problems related to those codes, I read briefly about fuses and loose battery connections etc so I pop the hood to check the battery cable. At this point is when I notice my rad overflow seemed empty but upon a closer look it was overflowing and coming out the overflow like a pink milkshake. I go grab the mechanic and the first thing out of his mouth is now your going to need a new transmission. Don't have money for that so I take the truck to a friends a few blocks over to park it. Now I'm thinking What the heck just happened there's no sign of spillage before they take my truck but there was some on the ground after. Did they just fill my reservoir with trany fluid or what? Any help would be great thanks.

Allan In NE

No,

You don't need a transmission. The cooler in the radiator is leaking and the transmission is pumping it's fluid into the radiator.

Allan

ot2bnla

Thanks for the reply. Would you happen to know if the p0741 TCC code would be thrown if in fact the fluid in the rad was mixing? I'd like to rule out the fact that my truck came out of the GM dealership in a worse condition then it went in. My friend just called me and said there is no sign of Rad fluid in the transmission after he just dropped the pan. He is going to be replacing the rad and doing both a coolant flush and tranny flush just to be on the safe side. I'd like to note here my truck has been well maintained the past few years. Regular synthetic oil changes, all fluids have been flushed in the past 12 months by a shop.

Allan In NE

Change the fluids and clear the codes. Then just watch it for a few days. Doubt if your light comes back on.

Oh, and keep it away from that dealer. He obviously doesn't know what he's doing.

Finding a competent mechanic nowadays is somewhat "challenging"

Allan

ot2bnla

Just an update here.....
Upon flushing the external cooler and lines going into the tranny there is definitely signs of contamination and one of the lines seems like it's blocked. Possibly from a build up of the mixed fluids. They act like a gel when mixed. Blew out the lines the best we could. Currently in the process of putting everything together again. I'm going to rule out the dealer sabotaging my truck theory with the evidence of the coolent in the external cooler. Chop it up to defective rad and hope I still have life left with this tranny when all is said and done.

ot2bnla

Ok now the fun begins......
New radiator, new thermostat, new coolent. Flushed the transmission lines, new TCC solenoid, new transmission fluid, filter and gasket. Have I forgotten anything? I don't think so but still no dice. Switches from 1st to second fine, reverse is better then it was before but it flares up in third and can't get it into fourth. Tried going on the express way with it and it revs up to 4000 rpms at 100km/hr or 60mph if your American. Any ideas before I drop the transmission?

Allan In NE

Was the pan full of soot?


Probably burnt it to the ground with the low oil level.


Allan

ot2bnla

The oil was dirty, about 2-3L in the pan when we dropped it. No signs of metal what so ever.

ot2bnla

Recommendations for a p0741 code suggest there is chips, sediment, or debris plugging the converter clutch signal orifice cup plug in the pump cover. The debris can block converter feed oil that is normally used to move the converter clutch valve and apply the TCC. Disassemble the pump, clean the converter clutch signal orifice cup plug in the cover and clean the facing area of the pump body.Also, verify free movement of the converter clutch valve. #PIP4329B

Sounds reasonable but definitely a long day.....I'm open to suggestions.

Allan In NE

Are you sure this unit isn't in default? That blocks everything above 2nd gear.


Allan