Hello. I have a 1993 Bronco with 108,000 miles. Recently, she started vi brating at around 30-40mph when under a load. It gets worse on hills and such. The vibration used to be erratic, but now is always present at the above speeds. I tried to wobble to driveshafts with my hands, but they seemed tight. Also, (I don't know if this is related or not) she will often die when put into reverse.
Any help with this problem is greatly appreciated. Thanks for your help!

 

Is there some reason why nobody has responded?

 

pull codes, fordfuelinjection.com will show you how. have you checked tranny fluid with rig running? tires might need rebalanced as well.

 

I'm going on the assumption that you have the E4OD transmission, if not then disregard. When the vibration starts, tap the brake pedal lightly. If the vibration stops for a short time then comes back, most likely is a slipping lockup clutch in the torque converter. Pulling the trouble codes should help confirm this, there are a couple that show up. When my 94 first started showing this symptom, I flushed the transmission fluid and the problem cleared up for a while then returned. Bad news is the only way I've heard to fix this is replacing the torque converter, which in my case means rebuilding/replacing the transmission since it has over 100k on it.

 

Codes first as Kem said. Its a LOT easier to diagnose and you are less apt to chase things that MIGHT be the problem.

 

Thanks for all the great response everyone . I guess I'll check the codes today.

Another note-I tried to spin the front driveshaft while I was under there and it spun for about 2 revolutions then wouldnt go anymore. The tranny was in park at the time. Don't know if this is normal or not. It was odd though, as the rear drivshaft wouldnt budge a mm from trying to spin.

I'll post what the codes read later today.

 

OK... WTF is the deal with Avatars!!! I tried for about 1/2 hour to save in every different .jpg, .gif, .pnd format and every time there was some problem!

(just venting)

 

The rear drive shaft will not spin unless the truck is in neutral with at least one tire off the ground. Do you have the stock automatic locking hubs on the front? If you do, that is why the front driveshaft rotated only two times, it takes them a bit to lock in.

 

OK- I pulled the codes out today. Man, that is really trying a persons patience in order to do so Anyway, I came up with: it's running rich, coil(s) are possibly bad, O2 sensor not functioning properly, and converter solenoid 3-4 is bad. Does any of this have anything to do with my vibration problem?? It seems like the best bet would be the converter solenoid, but how do I know for sure? I hope this doesnt mean a tranny rebuild. Any further adivce is much appreciated. THANKS

 

Mine had the infamous convertor shutter. I found another past thread where someone had bought a little red tube of "shutter stop" from O'reilly's and it had fixed the problem. I believe it is a friction modifier. I tried it and it totally took the shutter away (to my surprise and amazement). However, I didn't have the solenoid code. So, you may have more to deal with than I did. The O2 showing bad may be what is causing the rich condition. Oh, and if you are having a hard time counting codes, you can buy a code reader for about $35 (saw one yesterday at O'reilly's. It makes it alot easier. Good luck!

 

Thanks again for everyone who responded. I'm going to pull the driveshaft today and grease the joint under the rubber boot thingy. I'll post a response as to my success.

 

New update- I went under the car to remove driveshaft and discovered upon turning the bolts that the problem IS the double-cardon u joints. They were moving around and clanking when i only moved the driveshaft about 1/16th of a turn. Guess my original estimate was incorrect. I'm going to search this forum for advice in getting those darn bolts off w/o an air tool.

 

if that is not it read the thread
"tranny of fuel" that i started.. i had an issue with my torque converter.. a small tube of additive to the tranny fluid knocked out my vibration during acceleration up hill.

 

to help you find it.. the thread was last updated on 3-24 or here is a link to it. i dont know if the link will work correct though???
https://www.ford-trucks.com/forums/s...d.php?t=473615