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Transmission saga

968 views 8 replies 4 participants last post by  Ncford1 
#1 ·
Long story short, transmission rebuilt last fall by shop, likely cause of trans failure was water in fluid. So shop replaced radiator thinking water was coming from there. Now more water in fluid again, this time lots, fluid is pink and milky, last time was just trace water in fluid. So where else can water be coming from? Transmission dipstick, but where else?. Old radiator was never pressure tested to confirm leak. Now I'm having Transmission shop test current radiator for leak, and check everything else, but at the same time I'm going to check things too. I really don't want to rebuild this transmission again!
 
#2 ·
The only place the trans touches water is in the radiator. It could come in through the dipstick or the vent on top of the trans. Both of those are pretty high off the ground, you would need to drive through some pretty deep water to have it come in either of those spots.
 
#3 ·
Never been driven in water. Radiator was replaced when trans was rebuilt. The likelyhood of 2 radiators leaking into coolant seems improbable.
 
#4 ·
However Mr. Kovalsky's post is 100% accurate.

The only other way water could enter is a hole in the case or someone is putting water in it. Also inspect the transmission dipstick tube. I have seen one or two over the years that had rusted out severely leaving large holes and one was actually in two pieces.
 
#5 ·
Ok, just wanted to update this and report back. Water leak was from dipstick tube being broken right above o-ring allowing any rain, road water splash, or AC water leaking into trans. This really sucks because Trans was re-build 1 year ago and failed because of water in trans fluid, shop thought water was from radiator so it was replaced.(though radiator was never tested) 9 months later water in transmission and same shop replaced radiator, again thinking water that water was coming from there. What a waste of time and money! Finally though there is Zero water in trans as of the end of August.(I had to drain and fill the trans many, many times....all with mercon LV)

So, now there is and issue with the transmission not staying in overdrive. (I am sure from water being in trans) I have codes P0700, p0741, p1744 and tow/haul light flashing. All trans shifting is normal and smooth except it does not stay in OD. First start hot or cold, truck get up to about 50-60 and goes into overdrive/torque converter lock up and works for a short period(maybe 2 mins) then drops out and tow/haul light flashes. This happens 100% of the time. Fluid level is normal. Any ideas on where to start?
Thanks
 
#6 ·
The codes indicate that it DOES stay in overdrive, but the torque converter won't stay locked. P0741 means there is a mechanical problem (NOT electrical) that is keeping the torque converter from remaining locked. Since you had water in the trans my guess is that the friction material inside the torque converter has failed. It is also possible that the problem is a stuck control valve in the pump body or a bad seal on the input shaft.
 
#7 ·
I would have asked the trans shop HOW THEY MISSED the rotted out dipstick tube.
 
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#8 ·
First thought that came to my mind as well. They did R&R the transmission, didn't they? The cost of both radiators and the second failure you have should be on their dollar for misdiagnosis. I would be livid. Think about it another way, IF the fluid to coolant was leaking, there would be transmission fluid in the coolant as well as coolant in the fluid, and if that were the cause, the pressure from the cooling system would have blown out the transmission when you shut the truck down.
 
#9 ·
Yes trans was rebuilt last August. It's looking like it going to need another rebuild. I'm going to go to shoo this week.
 
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