Just got done scanning down through this Transmission thread...can't find anything that resembles the problem I'm having. Here goes:
I had the transmission overhauled in my 88 Town Car over the winter by my uncle, who was a Ford certified tech and automatic transmission specialist for over 40 years. I removed it from the car and brought it to him, he tore it down and rebuilt it using a combination of new parts, parts from my old transmission and some more from transmissions he had around his shop. I bought a new B&M Tork Master 2000 RPM stall converter and also installed a cooler in front of the radiator for some extra insurance. FWIW, my original AOD case was cracked around the bellhousing (I suspect it was due to the extra-long driveshaft crammed way too tight between the transmission and rear axle, that problem is featured in another thread) so the "new" transmission case is from an 83 T-Bird. All new gaskets and seals internal and external, valve body was done, new OD band, filter. Remainder of parts were best selected from the three different AODs that were combined to make one.
He calls me and tells me the transmission is ready, so I go pick it up. I bring it home, put a lick of paint on it and put it into the car. It goes in relatively well, no clearance issues with the flex plate and converter or anything else like that. Filled it up with ATF, cycle the gears, seems to be good. Checked TV pressure once warmed up, right on the money at 35 PSI in park with no cable adjustment, simply connected as-is.
Take it for a test run, the shifting is all kinds of messed up. No 1-2 shift at first, when it finally did upshift into 2nd, then the 2-3 and 3-4 were mushy as shit and piled up.
Figured it was just bawky from being freshly built. I go home, double check the TV pressure in NEUTRAL this time, bang on at 35 PSI. As the 1-2 shift was so delayed and a bit harsh, I drop the pressure to 30 PSI. Take it for another test run and wouldn't you know, it was behaving like there was zero TV pressure. Early, soft, mushy shifts, no downshifting at all under WOT, starting off in 2nd gear, etc.
Go home again, check TV pressure in neutral, bang-on 30 PSI. Based on how it was acting at 30 PSI, I shorten the cable to bump the TV pressure to 40 PSI.
Another road test, another complete failure, albeit a bit better than at 30 PSI. Upshifts are OK, (though not enough 'slip-bump' for my liking) won't go into OD at WOT, but no forced downshifting at any speed from any gear. Still acting like the TV pressure is too low. I verify the TV pressure to be 40 PSI at idle in neutral with the block on the cable between the crimped slug at the end and the square plastic adjustment sleeve. With it removed (when spec is between 0-5 PSI) my transmission is running closer to 30 PSI.
I get pissed off with it, pull the cable so short as it will go. Lock the white tab in, TV pressure is showing >50 PSI at idle now (no block). Revving makes it go in excess of 80 PSI. I then remove the gauge, road test again. This time the 1-2 shift is perfect, but 2-3 is still too early/soft. 3-4 backout shift happens at just under 35 MPH. Light throttle 3-4 shift happens just under 40 MPH. At 50-60 MPH 3-4-3-4-3-4 shift hunting on a slight grade is brutal. A forced 3-2 downshift will not happen over 15 MPH, making for some pretty embarrassing trips up steep hills, unless I do the AOD shuffle and manually haul it down into low gear. 2-3 shifts are almost immediately after the 1-2 shift at about 20 MPH unless I got the hammer down.
Has anyone else encountered this type of behaviour from an AOD? My next step is to set up the TV pressure gauge and leave it in place while I drive, just to observe what it does as it's acting like the TV pressure is dropping drastically once the transmission is placed into gear. Not that it will really prove anything, as all the specs for TV pressure are given for when the car is hot idling in neutral...
I really don't feel like taking that transmission out again...I only just got the rust, dirt and crap out of my eyes from putting it back in Easter weekend. Sick of doing everything right and still not being able to make something work as it should, and having to do stuff over and over and over again...
Fluid level is good, if anything might be slightly overfull. No leaks. Engine is running very nicely, FWIW it's an HO converted 5.0. Upper intake is stock, EGR spacer is bored out to 58 mm to match the 86 Mustang TB, which has the throttle linkage flipped. Old transmission wasn't like this, if anything it built up too much TV pressure and had delayed/harsh upshifts, no slippage unless it was cold and slightly overfull on fluid, and was noisy in gear. Glad I addressed it when I did, as the case was almost split in two from the crack along the bellhousing. Much longer and it probably would have broken in two and left me stranded on the side of the road like an asshole.
I had the transmission overhauled in my 88 Town Car over the winter by my uncle, who was a Ford certified tech and automatic transmission specialist for over 40 years. I removed it from the car and brought it to him, he tore it down and rebuilt it using a combination of new parts, parts from my old transmission and some more from transmissions he had around his shop. I bought a new B&M Tork Master 2000 RPM stall converter and also installed a cooler in front of the radiator for some extra insurance. FWIW, my original AOD case was cracked around the bellhousing (I suspect it was due to the extra-long driveshaft crammed way too tight between the transmission and rear axle, that problem is featured in another thread) so the "new" transmission case is from an 83 T-Bird. All new gaskets and seals internal and external, valve body was done, new OD band, filter. Remainder of parts were best selected from the three different AODs that were combined to make one.
He calls me and tells me the transmission is ready, so I go pick it up. I bring it home, put a lick of paint on it and put it into the car. It goes in relatively well, no clearance issues with the flex plate and converter or anything else like that. Filled it up with ATF, cycle the gears, seems to be good. Checked TV pressure once warmed up, right on the money at 35 PSI in park with no cable adjustment, simply connected as-is.
Take it for a test run, the shifting is all kinds of messed up. No 1-2 shift at first, when it finally did upshift into 2nd, then the 2-3 and 3-4 were mushy as shit and piled up.
Figured it was just bawky from being freshly built. I go home, double check the TV pressure in NEUTRAL this time, bang on at 35 PSI. As the 1-2 shift was so delayed and a bit harsh, I drop the pressure to 30 PSI. Take it for another test run and wouldn't you know, it was behaving like there was zero TV pressure. Early, soft, mushy shifts, no downshifting at all under WOT, starting off in 2nd gear, etc.
Go home again, check TV pressure in neutral, bang-on 30 PSI. Based on how it was acting at 30 PSI, I shorten the cable to bump the TV pressure to 40 PSI.
Another road test, another complete failure, albeit a bit better than at 30 PSI. Upshifts are OK, (though not enough 'slip-bump' for my liking) won't go into OD at WOT, but no forced downshifting at any speed from any gear. Still acting like the TV pressure is too low. I verify the TV pressure to be 40 PSI at idle in neutral with the block on the cable between the crimped slug at the end and the square plastic adjustment sleeve. With it removed (when spec is between 0-5 PSI) my transmission is running closer to 30 PSI.
I get pissed off with it, pull the cable so short as it will go. Lock the white tab in, TV pressure is showing >50 PSI at idle now (no block). Revving makes it go in excess of 80 PSI. I then remove the gauge, road test again. This time the 1-2 shift is perfect, but 2-3 is still too early/soft. 3-4 backout shift happens at just under 35 MPH. Light throttle 3-4 shift happens just under 40 MPH. At 50-60 MPH 3-4-3-4-3-4 shift hunting on a slight grade is brutal. A forced 3-2 downshift will not happen over 15 MPH, making for some pretty embarrassing trips up steep hills, unless I do the AOD shuffle and manually haul it down into low gear. 2-3 shifts are almost immediately after the 1-2 shift at about 20 MPH unless I got the hammer down.
Has anyone else encountered this type of behaviour from an AOD? My next step is to set up the TV pressure gauge and leave it in place while I drive, just to observe what it does as it's acting like the TV pressure is dropping drastically once the transmission is placed into gear. Not that it will really prove anything, as all the specs for TV pressure are given for when the car is hot idling in neutral...
I really don't feel like taking that transmission out again...I only just got the rust, dirt and crap out of my eyes from putting it back in Easter weekend. Sick of doing everything right and still not being able to make something work as it should, and having to do stuff over and over and over again...
Fluid level is good, if anything might be slightly overfull. No leaks. Engine is running very nicely, FWIW it's an HO converted 5.0. Upper intake is stock, EGR spacer is bored out to 58 mm to match the 86 Mustang TB, which has the throttle linkage flipped. Old transmission wasn't like this, if anything it built up too much TV pressure and had delayed/harsh upshifts, no slippage unless it was cold and slightly overfull on fluid, and was noisy in gear. Glad I addressed it when I did, as the case was almost split in two from the crack along the bellhousing. Much longer and it probably would have broken in two and left me stranded on the side of the road like an asshole.
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