Here's a little followup to a thread from back in March:
After discussing the transmission "spitting" issue with my "mechanical team" (Jim the mechanic and Logan the transmission builder) it was suggested
that I take a second look at my transmission vent hose routing. I had the hose going directly from the vent elbow on top of the transmission, to the
outside of the frame on the left side, going downhill all the way.
The theory was that this routing was somehow creating a siphon condition that was actually sucking fluid out of the vent. It really didn't make
sense, since the vent is at the top of the transmission and the only thing that should come out of it would be a little air in the form of pressure
relief. I went with their suggestion and put a longer hose on the vent with kind of a reverse trap in it. In other words, I routed the hose up
almost to the bottom of the floor, tying it to the back of the step, before running it out the side.
Problem solved.
On our 950 mile Summer trip last month, no fluid was lost from the transmission, in spite of several long pulls up 6% or steeper grades in second gear
(at temperatures well in excess of 100 degrees). Part of that was the same route (I-17 north of Phoenix) where I had the problem back in March.
There were several shorter trips in between those two, but I didn't want to draw any conclusions until I took a longer trip.
Hope this helps if anyone else has experienced this problem with their transmissions.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
After discussing the transmission "spitting" issue with my "mechanical team" (Jim the mechanic and Logan the transmission builder) it was suggested
that I take a second look at my transmission vent hose routing. I had the hose going directly from the vent elbow on top of the transmission, to the
outside of the frame on the left side, going downhill all the way.
The theory was that this routing was somehow creating a siphon condition that was actually sucking fluid out of the vent. It really didn't make
sense, since the vent is at the top of the transmission and the only thing that should come out of it would be a little air in the form of pressure
relief. I went with their suggestion and put a longer hose on the vent with kind of a reverse trap in it. In other words, I routed the hose up
almost to the bottom of the floor, tying it to the back of the step, before running it out the side.
Problem solved.
On our 950 mile Summer trip last month, no fluid was lost from the transmission, in spite of several long pulls up 6% or steeper grades in second gear
(at temperatures well in excess of 100 degrees). Part of that was the same route (I-17 north of Phoenix) where I had the problem back in March.
There were several shorter trips in between those two, but I didn't want to draw any conclusions until I took a longer trip.
Hope this helps if anyone else has experienced this problem with their transmissions.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member