'93 351, E40D, lots of miles... I'm experiencing very hard vibrations, really more of a shudder when in gear and underpowered.. for example, when cruising at highway speed & the OD gets settled in.. If I add power once the vibration starts, it gets worse. If I let off the gas THEN add power, it goes away.. Doesn't seem to be associated with a certain speed or gear, I've noticed it anywhere between 30 mph & 70 mph, and the vibration is always at the same frequency. (sounds the same every time) Seems to always happen around 1500-1600 rpm..

I've accounted for almost all the usual suspects: The rear driveshaft is new (no change) and I've tried removing the front driveshaft..

I've recently done other work that can be counted out as well... new wheel bearings all around, both front and rear diff are clean & tight with new fluids, new ball joints, new front axle u-joints, front hubs cleaned & replaced, new drums & rotors all around, tires rebalanced, changed tranny filter & fluid (except torque conv), new plugs & wires, new Distributor cap & rotor.. I had already planned on making these repairs anyway & just figured that one of these would take care of the vibration, but now I'm pretty much baffled...


I've got two ideas left:
1- Bad Torque converter
2- A few years ago I had an S-10 that acted similarly due to weak spark/faulty plug wire.. The only ignition part left is the coil, so perhaps a weak coil could be bogging under certain fuel ratios..


Please bring forth the ideas (and of course the hazing!!))

Thanks,
FamilyGuy

 

Does the vibration seem to come from the front (steering wheel) or the back (seat of the pants)?

Based on your troubleshooting so far, I think that it is an internal transmission problem and could very well be the torque converter. I suppose that transfer case problems could cause it as well, but I've seen this happen more frequently with automatic transmissions.

If you have the facilities to pull your tranny, you might want to throw a new torque converter on and see what happens. If you take it to a shop you will have a hard time finding anybody to just replace the torque converter and they will try to sell you a tranny too, although it might end up needing one. But if you can drop the tranny and put in a new torque converter then it woiuldn't cost that much, and even if you end up needing a tranny then you would still need the new converter anyway.

 

Just had my engine codes checked again... This time I got a new one...
628 -- Torque Converter lock-up problems.. I had checked my codes recently, but apparently it wasn't previously bad enough to generate a stored code..

Anyhow, it seems as though this is the culprit.. I'm going to plan on replacing the torque converter as soon as I can get the time... I've got access to a lift at a self-help auto shop on a military base, so I'm going to try to do it myself..

I've got the chilton to guide me, but I know sometimes you folks on the forum have some insight that make things like this easier, has anyone got any quick tips/techniques for a torque converter swap-out??

Thanks for the help,

FG

 

There's no real "easy" way to do it, but if you have access to a lift and a tranny jack then it will be much, much easier than trying to do it in the driveway up on blocks.

I once replaced a cracked flywheel on a 79 Cadillac, without dropping the tranny. I had a lift and a tranny jack, and I was able unbolt the driveshaft from the rear diff and then remove all of the trans bolts and a couple of other things, and use the tranny jack to move the tranny back enough to get in there and do the work. So technically I "removed" the transmission but the hard part is physically wrestling it out from between exhaust and other things, and I didn't have to do that. The whole job took about an hour! I started after work on Friday night and was done in time to take my wife out for dinner in the car. I don't know if you will be able to make enough room to do the converter, but it can't hurt to try, since you will have to drop the tranny anyway if you can't do it that way. A lift, a tranny jack, and some air tools and it's a fairly easy job.

On jackstands in the driveway, all I can say is "better you than me!" Been there, done that, ain't doing it again. That's what transmission shops are for.

 

you just might check your constant velosity joint before you get into your tranny I had the same thing in my 79 bronco thought it was the torque converter too but the cv joint was just going bad found the problem as we were leaving for the indy jamboree mgicfngrs

 

See if they have a tranny jack there as well. You will need it. It's basically a tall jack on wheels that extends up as high as needed to get under the tranny and has "arms" on it so you can lock on and "grab" the tranny and position it perfectly. Usually the tranny jacks also have smaller lift and tilt adjustments at the top so you can put the tranny in exactly the right angle and slide it right out and back in, with the wheels on the jack. It's pretty much a necessity if you are using the lift, I don't know how else you would do it on a lift unless you were very, very, very strong.

 

It's your converter (told you so , you have the skills to pull it without a problem. The only hang up on changing a converter is making sure it is seated properly before you reinstall the transmission. These converters take some playing with before they fully seat. Take a good measurement or make a mental note of the current converter when you take off the bottom inspection plate. You will notice a very small amount of room/space between the back side of the converter and the bell housing. A very long extension with (what I call) a universal joint will help you get to the top bolts of the transmission. If I remember right, they are all 5/8 in size. Be sure to take off your starter, driveshaft and possibly the exhaust. The tranny should slide down and back enough for you to put in the new converter. I'll send you information on a good priced new converter that a guy sells on ebay. Oh before I forget, go to Ford and get four new converter nuts. Always replace the old ones with new ones when replacing the converter. They are a special lock nut and it is worth the couple of bucks to replace them. Be sure to grease your converter seal as well before installing the new converter. Anyother concerns you know my email and phone number.

 

I just had my torque converter replaced for the same problem. They also installed a transmission kit. There may a heavy duty torque converter available for your truck. That's what I had installed. And don't forget a tranny cooler if you don't have one already!! Also, if the funds allow it, you might want to consider synthetic tranny fluid. I must say, my tranny runs like new and shifts like a dream!! Good luck.

P.S. After you drop the tranny, consider replacing your rear main seal on the engine.

 

Parts came in last night & I got the torque converter swapped out.. Sure 'nuf, no more nasty vibration!!

Thanks for all your input,
FG

 

I had the same problem on my 302 93 bronco with the EOD4 at 200,000 miles. It was the torque converter and i took it in to get the tranny fluid purged and then had the pan dropped and filter replaced. It now has 270,000 on it and never had to replace the converter. I have changed the fluid since then at about 240,000 when it started to chatter slightly (not as bad as first time though). I don't think it was necessary for you to swap out the converter just yet.

 

Glad to hear it Familyguy. She should run like a top now!!! I'm just having a hard time paying $2.35 a gallon for gas right now. I think I'm gonna make one of my Broncos hydrogen powered. This summer will be a good time for that.