Ford Transmission :: 1979 F150 - Lost Reverse And Won't Stay In High Gear
Oct 28, 2012
79 F150 400/C6 2wd. Loss of reverse and it doesn't want to stay in high.
Strange thing happened today. I took my truck on it's longest test drive since rebuilding the transmission. It was about 25 miles. I got to the junk yard just fine and it was running just fine when I left. I went through a drive through to grab a burger and headed home. That's when it started acting funny. It shifted fine 1st to 2nd, then 2nd to 3rd, but it wouldn't stay in 3rd. It would shift into high, but the slightest bit of throttle and it would shift back into 2nd and eventually got so bad that it just stayed in 2nd, so I had to return to the town I was leaving.
I drove to an autoparts store nearby. I decided to move where I was parked and when I put it into reverse, nothing was there. It rolled back. I drove it to the new spot and called for a tow truck. Weird thing is that reverse worked just 10 minutes earlier when I left the junk yard. When I got it home 2 hours later, it backed up under it's own power. I let it cool down completely and took it for a test drive and it drove perfectly. I have a few theories or questions:
Kickdown rod: Can it be in such a position that it could take away reverse? I would assume that if the spring wasn't returning it all the way forward that it wouldn't have shifted from 1st to 2nd properly. I ask this because I am not using the Holley spring mount and I'm wondering if the wrong spring set up allows the kickdown to be partially activated.
Fluid: What fluid are you suppose to use after a rebuild and what fluid can't you use. Mercon V says it supercedes earlier fluids, but is that wrong?
Am I wrong to assume that if fluid was the problem that I would have had problems with 1st and 2nd?
Cooling: What are signs of hot fluid other than smelling it. Once again, assuming I would have problems with all gears if fluid was too hot.
My guess is that something is sticking in the valve body, but before I drop the pan and pull out the valve body, I want to make sure all other avenues are exhausted.
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I am looking to change out my manual transmission in my 79 f150. I want to put a 5 speed in it but still keep my manual clutch. I have a 300 engine that I also want to keep, can I just put a late 80's early 90's 5 speed transmission in it and keep my original bell housing?
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Friend lost reverse and truck shakes at 35 and above seems like it needs a new transmission. What years are a match for this transmission and any other models trans match?
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I used my truck in 4x to pull a couple of little stumps. Nothing major, just put it in 4l more or less to keep from tearing up the yard. Noticed a couple of weird things today. For a minute had a good pull to the right. Just felt "weIrd" in front end. For lack of a better explanation. Jacked up and checked for play, nothing unusual. Took off the tire and checked other stuff and couldn't find anything. Lubed up joints etc and drove later. I'm hearing a slight " clanking" noise in front. I know it's got something to do with the 4wd but I don't know where to start.
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I have a 2000 F150 5.4L with 157k miles on it. I think it has the 4r70w trans. The transmission has started holding 2nd gear too long before shifting into third. Throttle position doesn't matter, it does it even under light throttle. I do not have a check engine light. I have owned the truck since new and the trans fluid has been changed 3 or 4 times. The fluid looks pretty good now, not burnt or anything. The truck has been sitting in the garage a lot over the past 2 years, I drive it at least once a month and have put maybe 2000 miles on it this year. It shifts fine through the other gears, just 2-3 has an issue. Truck has the towing package.
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91 F-150 4x4 with AOD. OD,D,1st gear. The truck will idle fine, but when I put it into gear it seems like it is locked in in either drive or reverse. Its hard to stop at lights or stop signs and boggs the engine down and has no low end power. When in neutral it is fine. I have replaced the torque converter with a new one, no change. I replaced the valve body with a constant pressure body as well and still no change. Is there anything else that could keep the thing locked up? The smaller inside overdrive shaft looked good and slid in and out easily. Is there any kind of solenoid in the AOD that would cause this or if vacuum has any role in this problem...
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My 95 f150 stalls in reverse. It goes fine forward and idles fine in reverse but if I give it quite a bit of gas it starts stalling. We've put a new mlps and that didn't fix it. Then they thought it was the convertor so I got the trans rebuilt and still no change. I'm about to pull my hair out over this deal. I don't even have enough power to back up a trailer or back up a hill.
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When truck warms up I lose reverse. I changed fluid and tranny filter and I am still having the problem...
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I have a 1979 Ford F150 1/2 ton P/U XLT, 4WD 6.6L 2BL OHV 8cyl that I'm trying to put A/C back in. The truck had factory air, but the evaporator is the only original part in this setup (along with the controls inside the cab on the dashboard).
The new compressor is working. All the pressures look good (the low side is around 35 to 40). But we're finding that the air out of the vents is only dropping 20 degrees max. We've checked to see if the blend door was not working and it was getting heat from the heater core. We blocked off the heater core completely with the same results. It just doesn't seem to be getting cool enough. The large fittings on the firewall should be cold (maybe 40 degrees), but it's only cooling to about 79 degrees, about a 15 degree drop.
We cannot see into the evaporator box to see if there is an expansion valve in the system, but we did not put an expansion valve in with the new system we put on.
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1979 ford f-150, 460 w/ 4bbl. Carb recently rebuilt by professional, but on cold mornings (in particular) runs rough even after a little warm (just like me), like the choke isn't clicked or clacked (couldn't resist) off. Can the choke flap and mechanism be gunked up, needs some cleaner applied?
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I have been fixing up my 77 F150 since I got it in January and it's really starting to look nice! I love this truck, but I have noticed a clunk sound when I put it in reverse and also a same if not similar sound when I'm driving and slow down. It makes a clunk sound when it shifts to a lower gear, (automatic). Now, I was thinking it was a U joint at some point and crawled under there and started to grab them and see if there was any play in any of the spots but found no play. I checked it a few times, thinking well it could be just the point the U joint stopped and that would explain no play but after a few times of crawling under I still never found any.
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I have a 89 f-150 xlt with what i believe is the m5od (4 speed with O.D) transmission and the 5.0 motor, the trans has been whining since I've owned the truck and it started popping out of reverse on me a couple months ago, now i have to slam it into gear to make it go anywhere even when I am going down the road! The clutch is fine but the trans is hanging up, anyways i have a granny gear transmission a buddy of mine gave me out of an 85 f150 that had the inline 6 if i take the bell housing off of my transmission can i put the internal slave cylinder on that transmission? Will it work or will i have to find a way to put an external slave cylinder on it?
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I have rebuilt my transmission but it keeps burning up reverse high clutch plates. It has burned up two sets so far. I am thinking that it might be something stuck in the valve body.
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I have a '79 F150 4wd and was wondering what would indicate a caliper needing replacement. I'm already going to replace everything on my rear brakes, they are completely trashed. However, the fronts seem OK, NO indications of leaks or seizing both sides of the rotors appear to be evenly "used" I guess. The inner pads do seem to be thicker than the outer pads is this normal? Anything I should be specifically looking for before I have the rotors turned and put a new set of pads on?
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1998 Ford f150 172984 miles automatic with 4x4 runs and drives transmission is going out will not hit 3rd gear have to drive in 2nd. Is there a fix without pulling the transmission?
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My 94 F150 has been actingup lately with the 4r70 transmission not shifting into 3rd gear or above. I replaced the MLPS sensor and re pinned the plug as per the instructions with the switch.The old sensor had the plug on the side, same type of plug, but wires indifferent spots. Truck wouldn't start like that, so repinned to match the instructions. I couldn't get the neutral mark to 100% line up as there is not enough adjustment, but it is very close.
The old plug had
32-298-140-33
57-199-359-463
I switched it to
57-359-199-463
33-140-298-32
Then tried
463-359-199-57
33-140-298-32
Truck still won't shift to 3rd, overdrive off button doesn't light up and itwon't start in neutral. I tested the ground at the connector and it lights up atest light connected to the pos bat cable with no issues.
Back up lights won't work, but flicker as going from R to N, so I suspect that is due to the fact I couldn't get the marks to line up 100%, but i'm not worried about that now.
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So finally got my truck running due to a fuel issue. Anyways been driving it for a week or two now, and I have a strange problem idk if it has been covered here or not.
Driving around tow etc if you come to a light or whatever and stop the rpms stay at 800rpm. Now if you shift it out of gear and back into drive the rpms settle back down around 650. Where is should be.
My guess is the torque converter is not disengaged all the way when it stuck at high rpm (800-900) for this situation. No cel, slippage, or crazy noises
2002 7.3 power stroke all stock right now @160k black crewcab
Previous owner had a tunner on it but not anymore. Could it have smoke the trans???
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It's a 1988 with a 3.0 engine and an automatic transmission. It doesn't want to shift. I can make it shift manually, but if I leave it in OD, it wants to stay in 1st gear . If you fiddle with the accelerator, you can get it to shift. Then it wants to stay in 2nd, and so on.
Like I said, if I use the gear selector to manually shift, it will go to all four gears just fine.
My thoughts are a vacuum leak (a big one) or a faulty vacuum modulator at the transmission. No, the vacuum line to it doesn't have tranny fluid in it, but I replaced it, and I wonder if it's bad. Yes, I made sure to put the little metal pin/link back in it.
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My manual transmission got stuck in 4th because of a melted oil trough sticking between the gears. I got all the plastic out, and the dog clutches/collars are "free." But, I don't know how to put the gears back into neutral. When it's reassembled, the stick doesn't work to change the gears. How can I get the gearbox back into neutral?
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My 82 f150 4x4 302 c6 trans is acting up. My c6 is slow to shift into any gear when I shift the column shifter, after a moment it jerks into gear, also it doesn't seem D is doing anything but all the other gears seems to function manually or auto.
Fluid level looks ok, maybe a little high on the dipstick. I'm going to check the modulator and do a fluid/filter change but looking for a link to the band adjustment screw ?
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I have a 2007 F150 FX4 with 105K on it. When it goes from 2nd into 3rd, it acts like it's in neutral. There's nothing there. This is in "D" with "OD" on. If i turn OD off, it will wind up and grab 2nd again and will coast if I let off the gas. Also, if I manually shift into 2nd, it will engage 2nd and I'll have engine braking if I let off the gas.
The trans fluid was full and bright red as is should be with no burnt smell to it.
I dropped the pan and the magnet was a little fuzzy with some metal filings but there was no metal laying in the pan. I also dropped the valve body and there were no broken snap rings and the e-clip on the OD servo was intact. The valve body was also clear of anything that shouldn't be there. I'm hoping that I can replace the shift solenoid and that will solve my issues.
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