I'll put the TL
R at the top for quicker answers. Long version below, mostly for me to write it all down somewhere because it's been bouncing in my head all day like a damn pachinko machine.
There is a slight vibration when my torque converter locks up. I've read the searches and done the tests and I can produce the symptoms with some confidence. When the TQ locks up, there are occasional pulses of vibration with a low growly sound right underneath my feet. It doesn't shake the truck or affect performance, it could almost be attributed to road feedback if one wasn't paying attention. If I had the radio on I might not even notice it. How big a deal is it to keep driving my truck as I continue to investigate this issue? I know nothing about automagics.
Braindump:
So my 93 F350 NA IDI 4WD has an interesting situation going on I need a few second opinions on. When I bought this truck OD was claimed to have 170k, I've since determined it's more likely 270k but the first digit is barely readable. Ohwell, I wasn't concerned either way. Transmission was rebuilt recently, within 10k miles. Still trying to get documentation from the guy who did it but it's not like some pro shop it's just a guy who rebuilds trannys, ya know? who knows what he knows. He said he beefed it up and added a shift kit. I have been keeping an eye on it and I have a shop I trust to take care of it should the need arise. I know literally nothing about automatics, this is my first vehicle to have one so I'm kind of paranoid about it, but I'm playing it cool on the outside since it hasn't messed up yet and I'm learning more as I go.
First issue is the pan seeps a little. I snugged up the bolts carefully with a small torque wrench to not overtighten. All of them need some snugging, but more and more so towards one central corner where there is a bolt that the hole is stripped. Can't get it tight enough to stay tight, so I don't think the pan will ever stay tight until that is repaired. Doesn't leak hardly enough to even drip, so it hasn't seemed like an urgent fix, just something to do when dropping the pan next.
Second issue is I notice the lines to the oil cooler are leaking a little right at the cooler. I've been keeping an eye on the oil levels due to pan seepage, so I know it's not leaking much, so I cleaned up the fittings and snugged up the clamps and am keeping an eye on it. Haven't driven it enough to really kick in the cooler I don't think. I don't know what temp the cooler starts cycling, or if it just does it always? I should probably know that from research. Either way, it isn't leaking yet.
Right around this time I realize the brake lights aren't working so I looked into it and discover they have LED bulbs, but they are not working. I swap them back to regular old bulbs instead of figuring out whatever wiring resistors need to be added to make the led bulbs work. Problem solved. I'm including this because of what I've discovered after researching the problem that happens next.
Next time I drive the truck I notice this pulsing vibration at certain speeds with the throttle applied. It's not in the steering, it's in the driveline. I can feel it in my feet, it sort of rolls across as it pulses. I don't know if that makes any sense. My first instinct is I have a ujoint issue, as they've been on my list to do. In fact I have just picked up the replacements. So i spent the day swapping the ujoints, as I have a job tomorrow I need the truck for. Figured it would be just in time! Nope. Doesn't solve the problem.
So after a lot of head scratching and research and test driving I discover that the vibration is occurring when the torque converter is locking. I was able to confirm this driving, as the vibration would only occur after shifting into 3rd or 4th (OD). If I let off the gas it stops, as soon as I press the throttle again I can literally feel the torque converter lock, and then it starts vibrating. It doesn't do this at all in the slightest at slower speeds in 1st or 2nd, so I am pretty confident it isn't a misfire. I did have the pump and injectors rebuilt by this real high-quality guy most of you probably have heard about
But then I learn that LED's can cause havoc with torque converter lockup because of the voltage drop on the same line the TQ uses to know when you press the brake. I bet the torque converter just was never locking before and I didn't really understand that it wasn't because I'm not used to auto's?!?! Is that possible? My mpg's have been lower than I thought they could be, but I was just assuming it was little things like old ujoints, wheel bearings, etc all adding up to lower mpg's. It's a big truck, I'm not used to working on this type of equipment so I didn't have a lot of concern until I had fixed the little things. I don't put a lot of highway miles on it. I've done a few bigger trips, but it's mostly just around town. I do landscaping, so it is hauling weight and often a dump trailer. So I might not have really noticed much that the TQ wasn't locking because I am usually driving below 50mph. When I was really paying attention I could feel it at like 35-40 cuz I would be in 3rd around then, so if it was going on before I would have noticed it. The fact that it started literally the same day I swapped the brake lights really has me wondering.
So is it possible that I'm noticing torque converter lockup for the first time? I can really feel it now, I thought at first my transmission was slipping or something, but it was just the sensation of the secondary "soft shift" of the tq locking I guess. Am I making sense or am I a crazy person? I'm wondering if there is an issue with my torque converter and I just never knew it before because of the LED lights making the TQ never lock? It is just a slight vibration, not what I see described as "shudder". It feels like ujoint vibration, which is why I went that route first. It isn't constant, but whenever the tq is locked, it just occasionally has what I call a rolling pulse of vibration that stops the second I let off the gas, and then starts back up as soon as I feel that lockup sensation after hitting the gas again. I can feel it in my right foot first, then both feet, then my left foot. It has a low grumbly growl and vibration. You could almost ignore it but I can't ignore stuff like this. No problem with power, shifts are fine. At least as far as I know, I've never driven a truck this size before. Mostly just gassers, 3/4ton, etc. This big beast seems like a monster but maybe I'm missing out on performance I should be expecting? I don't know. I doubt it. I think the engine is running like a champ. It hasn't stumbled once since getting the IP and injectors done. It really just seems like whenever the converter is locked it does the vibration thing, and it's only happening now for the first time because I just swapped the taillight bulbs back. I guess I could put the led's back in and test drive to see if it goes away. When I have time.
But I'm just going to drive the truck tomorrow for work and assume it isn't going to fry my transmission? Unless I wake up and see people here giving me a resounding "don't you dare drive it until you fix that vibration!". My boss understands if we have to reschedule, it's a low priority job but it would be nice to do tomorrow when the sun is shining. And I'd feel real stupid rescheduling last minute like this because I've never felt my torque converter lock up before and I don't know what it is supposed to feel like, haha!
Hoping to get some feedback from people who are more knowledgeable on these things.
I was thinking in the morning I would get under and check the wires and plugs and stuff again. I've looked it over before and had to repair the ground wire going to the trans oil temp gauge that had been added. Cleaned up the gunk around everything that looked important, but all the wire connectors seemed intact and in good order. Might as well pull the connector and clean it with some of the magic electrical cleaner and grease it up with that electron lubricant, get the volts really zippin. Open to any other quick last minute checks worth trying.
R at the top for quicker answers. Long version below, mostly for me to write it all down somewhere because it's been bouncing in my head all day like a damn pachinko machine.There is a slight vibration when my torque converter locks up. I've read the searches and done the tests and I can produce the symptoms with some confidence. When the TQ locks up, there are occasional pulses of vibration with a low growly sound right underneath my feet. It doesn't shake the truck or affect performance, it could almost be attributed to road feedback if one wasn't paying attention. If I had the radio on I might not even notice it. How big a deal is it to keep driving my truck as I continue to investigate this issue? I know nothing about automagics.
Braindump:
So my 93 F350 NA IDI 4WD has an interesting situation going on I need a few second opinions on. When I bought this truck OD was claimed to have 170k, I've since determined it's more likely 270k but the first digit is barely readable. Ohwell, I wasn't concerned either way. Transmission was rebuilt recently, within 10k miles. Still trying to get documentation from the guy who did it but it's not like some pro shop it's just a guy who rebuilds trannys, ya know? who knows what he knows. He said he beefed it up and added a shift kit. I have been keeping an eye on it and I have a shop I trust to take care of it should the need arise. I know literally nothing about automatics, this is my first vehicle to have one so I'm kind of paranoid about it, but I'm playing it cool on the outside since it hasn't messed up yet and I'm learning more as I go.
First issue is the pan seeps a little. I snugged up the bolts carefully with a small torque wrench to not overtighten. All of them need some snugging, but more and more so towards one central corner where there is a bolt that the hole is stripped. Can't get it tight enough to stay tight, so I don't think the pan will ever stay tight until that is repaired. Doesn't leak hardly enough to even drip, so it hasn't seemed like an urgent fix, just something to do when dropping the pan next.
Second issue is I notice the lines to the oil cooler are leaking a little right at the cooler. I've been keeping an eye on the oil levels due to pan seepage, so I know it's not leaking much, so I cleaned up the fittings and snugged up the clamps and am keeping an eye on it. Haven't driven it enough to really kick in the cooler I don't think. I don't know what temp the cooler starts cycling, or if it just does it always? I should probably know that from research. Either way, it isn't leaking yet.
Right around this time I realize the brake lights aren't working so I looked into it and discover they have LED bulbs, but they are not working. I swap them back to regular old bulbs instead of figuring out whatever wiring resistors need to be added to make the led bulbs work. Problem solved. I'm including this because of what I've discovered after researching the problem that happens next.
Next time I drive the truck I notice this pulsing vibration at certain speeds with the throttle applied. It's not in the steering, it's in the driveline. I can feel it in my feet, it sort of rolls across as it pulses. I don't know if that makes any sense. My first instinct is I have a ujoint issue, as they've been on my list to do. In fact I have just picked up the replacements. So i spent the day swapping the ujoints, as I have a job tomorrow I need the truck for. Figured it would be just in time! Nope. Doesn't solve the problem.
So after a lot of head scratching and research and test driving I discover that the vibration is occurring when the torque converter is locking. I was able to confirm this driving, as the vibration would only occur after shifting into 3rd or 4th (OD). If I let off the gas it stops, as soon as I press the throttle again I can literally feel the torque converter lock, and then it starts vibrating. It doesn't do this at all in the slightest at slower speeds in 1st or 2nd, so I am pretty confident it isn't a misfire. I did have the pump and injectors rebuilt by this real high-quality guy most of you probably have heard about
But then I learn that LED's can cause havoc with torque converter lockup because of the voltage drop on the same line the TQ uses to know when you press the brake. I bet the torque converter just was never locking before and I didn't really understand that it wasn't because I'm not used to auto's?!?! Is that possible? My mpg's have been lower than I thought they could be, but I was just assuming it was little things like old ujoints, wheel bearings, etc all adding up to lower mpg's. It's a big truck, I'm not used to working on this type of equipment so I didn't have a lot of concern until I had fixed the little things. I don't put a lot of highway miles on it. I've done a few bigger trips, but it's mostly just around town. I do landscaping, so it is hauling weight and often a dump trailer. So I might not have really noticed much that the TQ wasn't locking because I am usually driving below 50mph. When I was really paying attention I could feel it at like 35-40 cuz I would be in 3rd around then, so if it was going on before I would have noticed it. The fact that it started literally the same day I swapped the brake lights really has me wondering.
So is it possible that I'm noticing torque converter lockup for the first time? I can really feel it now, I thought at first my transmission was slipping or something, but it was just the sensation of the secondary "soft shift" of the tq locking I guess. Am I making sense or am I a crazy person? I'm wondering if there is an issue with my torque converter and I just never knew it before because of the LED lights making the TQ never lock? It is just a slight vibration, not what I see described as "shudder". It feels like ujoint vibration, which is why I went that route first. It isn't constant, but whenever the tq is locked, it just occasionally has what I call a rolling pulse of vibration that stops the second I let off the gas, and then starts back up as soon as I feel that lockup sensation after hitting the gas again. I can feel it in my right foot first, then both feet, then my left foot. It has a low grumbly growl and vibration. You could almost ignore it but I can't ignore stuff like this. No problem with power, shifts are fine. At least as far as I know, I've never driven a truck this size before. Mostly just gassers, 3/4ton, etc. This big beast seems like a monster but maybe I'm missing out on performance I should be expecting? I don't know. I doubt it. I think the engine is running like a champ. It hasn't stumbled once since getting the IP and injectors done. It really just seems like whenever the converter is locked it does the vibration thing, and it's only happening now for the first time because I just swapped the taillight bulbs back. I guess I could put the led's back in and test drive to see if it goes away. When I have time.
But I'm just going to drive the truck tomorrow for work and assume it isn't going to fry my transmission? Unless I wake up and see people here giving me a resounding "don't you dare drive it until you fix that vibration!". My boss understands if we have to reschedule, it's a low priority job but it would be nice to do tomorrow when the sun is shining. And I'd feel real stupid rescheduling last minute like this because I've never felt my torque converter lock up before and I don't know what it is supposed to feel like, haha!
Hoping to get some feedback from people who are more knowledgeable on these things.
I was thinking in the morning I would get under and check the wires and plugs and stuff again. I've looked it over before and had to repair the ground wire going to the trans oil temp gauge that had been added. Cleaned up the gunk around everything that looked important, but all the wire connectors seemed intact and in good order. Might as well pull the connector and clean it with some of the magic electrical cleaner and grease it up with that electron lubricant, get the volts really zippin. Open to any other quick last minute checks worth trying.
