30dodgeboy
put a 12V in 79 F250 4WD
- Joined
- Jun 8, 2010
- Messages
- 36
I just recently had major problems with the 47RH in my completely stock 94 4WD Ram. Put ~40,000 miles on this truck since I got it without any trans trouble so far (was told the trans was previously rebuilt at some point). I use it for daily driving and occasional towing of a 7000# car trailer (I don't use OD below 55mph when towing, and not at all if the terrain isn't flat).
I was pulling my car trailer with a car on it, and when pulling out of a toll booth I noticed the trans was slipping pretty bad at higher throttle. There was no place to pull over safely, so I continued driving it at less throttle - knowing that I was still inflicting more damage. In the next 20 miles the slipping got severe enough that the truck needed to be towed the rest of the way home. At that point, the truck would not move at all forward or reverse without 2000 RPM. So I pulled the trans out and tore it all apart...
The oil is black like engine drain oil and really stinks like burned oil.
No metal in pan, only a few flakes of clutch lining, magnet has some fuzz but overall pan is rather clean compared to the others I have been inside.
Front clutch plates look great, clearance is good, seals all intact.
Rear (forward) clutch plates look great, clearance is good, seals all intact.
Intermediate band is overall burned and about one square inch of lining flaked off.
Rear (lo/rev) band looks like new.
Sprag behind rear band is intact.
Intermediate clutch plates are smoked completely black and worn ~0.010" each. This pack was bottoming out against the OD piston (thickest OD piston shim was installed by previous rebuilder) preventing the spring from applying them properly.
OD (brake) plates somewhat burned, but should have still worked. OD piston seals intact. OD clutch pressure plate and backing plate were installed in wrong positions (by previous rebuilder).
Sprag in OD section is intact.
Both servos' seals are good, as well as the accumulator seals.
Sprag in torque coverter is operating correctly.
I blew compressed air into the front cooler line (in direction of flow) and (burned) oil came out cooler return line.
I am scratching my head on this one :nail: Slipping direct clutches would prevent reverse, but the OD sprag should still make the truck move forward...
Anyone have any suggestions???
I was pulling my car trailer with a car on it, and when pulling out of a toll booth I noticed the trans was slipping pretty bad at higher throttle. There was no place to pull over safely, so I continued driving it at less throttle - knowing that I was still inflicting more damage. In the next 20 miles the slipping got severe enough that the truck needed to be towed the rest of the way home. At that point, the truck would not move at all forward or reverse without 2000 RPM. So I pulled the trans out and tore it all apart...
The oil is black like engine drain oil and really stinks like burned oil.
No metal in pan, only a few flakes of clutch lining, magnet has some fuzz but overall pan is rather clean compared to the others I have been inside.
Front clutch plates look great, clearance is good, seals all intact.
Rear (forward) clutch plates look great, clearance is good, seals all intact.
Intermediate band is overall burned and about one square inch of lining flaked off.
Rear (lo/rev) band looks like new.
Sprag behind rear band is intact.
Intermediate clutch plates are smoked completely black and worn ~0.010" each. This pack was bottoming out against the OD piston (thickest OD piston shim was installed by previous rebuilder) preventing the spring from applying them properly.
OD (brake) plates somewhat burned, but should have still worked. OD piston seals intact. OD clutch pressure plate and backing plate were installed in wrong positions (by previous rebuilder).
Sprag in OD section is intact.
Both servos' seals are good, as well as the accumulator seals.
Sprag in torque coverter is operating correctly.
I blew compressed air into the front cooler line (in direction of flow) and (burned) oil came out cooler return line.
I am scratching my head on this one :nail: Slipping direct clutches would prevent reverse, but the OD sprag should still make the truck move forward...
Anyone have any suggestions???
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