Vibration after shift w/ light acceleration :( also check engine light on interstate

[4FordFamily]

1995 XLT 4.0 4WD - 188k miles

Sounds to me like a U-joint? Also at high(er) speeds, you can hear/feel it a little too... slight vibration like the tires are messed up but I took off my 24's, and put on my 15's for the winter and it does it still. It's getting worse.

Everything is/was balanced properly.

The main concern is when it comes out of 2nd and 3rd (I believe its both) and im going slow 30-40mph and im lightly hitting the gas, it vibrates severely (pretty severely) but if I so much as TAP on the gas the vibration goes away. Does not happen at interstate speeds when im barely hitting the gas.

Also: Trans MAY be shifting funny..but it has 40k on it so I doubt that's the issue? After 2nd or 3rd (never paying attention when it happens... it happens every 20th shift or so) it shifts like my freaking durango did... kind of rough and vibrates a bit.. but it could very well be the U-joint or whatever messing up (because it happens under light acceleration) so perhaps it's getting one NICE vibration in to make it feel like it shifts funny.

Im so sick of spending on my exploder, I just replaced a dang heater core, it needs ANOTHER alignment (not big wheel related, even after they were off it needs it every 5 minutes) and also today my check-engine light came on on interstate driving.. which is probably not correlated with the vibration?

It starts after an hour+ of 80mph driving, up to 90mph driving... as soon as I start slowing down a bit, it comes on.. and then comes off again about an hour later after city driving. Engine is NOT overheating and the oil pressure is fine (according to the gauges) Did this once after a 90mph 4 hour trip to St. Louis.

Trying to get those old baby to last for me but she's proving difficult!

 

[steveofire]

I had the same problem on mine and it ended up being the rear u-joint so i replaced all 3 and now it is all good again. Also go to Advance auto parts here 7340 Michigan Rd. Indianapolis, IN 46268 and they should have a scanner that you can pull your cel codes for free and see what is going on.

 

[4FordFamily]

I had the same problem on mine and it ended up being the rear u-joint so i replaced all 3 and now it is all good again. Also go to Advance auto parts here 7340 Michigan Rd. Indianapolis, IN 46268 and they should have a scanner that you can pull your cel codes for free and see what is going on.

how much did it cost for your U-joints?

Did you have all the symptoms mentioned?

 

[steveofire]

I belive the u-joints were about 15 and ? when you lay off the gas does the vibration go away or does it stay there. One way to check the u-joints is to climb under the truck and move the drive shaft right by the u-joints up and down and side to side and see if you have any play at all.

 

[4FordFamily]

I belive the u-joints were about 15 and ? when you lay off the gas does the vibration go away or does it stay there. One way to check the u-joints is to climb under the truck and move the drive shaft right by the u-joints up and down and side to side and see if you have any play at all.

Im illiterate with mechanics... lol

If I let off the gas it goes away as well, only does it under light acceleration right after a gear shift, mostly. And then a LITTLE bit at highway driving (sounds like more of a tire problem, but does this with both sets of my wheels)

 

[steveofire]

One thing to try is go out and start it up and put it in reverse and then go right to drive and back to reverse do this a few times and listen for any clunking when it goes into drive or right back into reverse.

 

[4FordFamily]

One thing to try is go out and start it up and put it in reverse and then go right to drive and back to reverse do this a few times and listen for any clunking when it goes into drive or right back into reverse.

oh yeah, lots of clunking. Been an issue for awhile, but the vibration is new.

I began to think it was normal!

 

[steveofire]

Ok call around to a couple of tire shops and most of the time they will do a free inspection on your truck and see if what they come up with.

 

[4FordFamily]

Ok call around to a couple of tire shops and most of the time they will do a free inspection on your truck and see if what they come up with.

im confused, so does it sound liek U joints?

 

[4FordFamily]

welp, today something completely screwed up and I had to tow my truck, AWFUL grinding noise in reverse or drive (it engaged, but makes awful noise when it goes in to either) the clunking was always there, so I suspected U joints, but now I'm lost. What do you guys think is wrong?

It grinded when I drove it, park worked at first, and then it started rolling backwards. Emergnecy brake didnt work, and I'm stressed out. No rear end fluid anywhere. Noticed what I think is a hose disconnected to the rear end?

Just before this happened, it started vibrating just after a shift in 2nd or 3rd, going 25-40mph. Tap the gas more, it went away, let off the gas, it went away. Just before it messed up on the way home, it started vibrating even when decelerating (no gas). Still, it went away when I accelerated. (So it only vibrated with LIGHT gas after shift, then started doing it even when braking/slowling down). It also vibrated and made funny noise on the interstate, but not 1/10 as bad. Felt almost like a wheel was off-balance (but just had them balanced).

4wd didn't fix anything it had the same probekms, but made awful grinding noises when taken in/out, and same from drive to reverse.

this sucks anybody have an educated idea?

 

[steveofire]

Boy with out looking at it i am at a lost for words i have never encountered this type of problem before. One thing you can do is get all 4 wheels off the ground and put it in drive and see if it is making the noise and see if you can find where it is coming from or just put it in gear with out the motor running and turn the tires and find the noise..

 

[uefear]

welp, today something completely screwed up and I had to tow my truck, AWFUL grinding noise in reverse or drive (it engaged, but makes awful noise when it goes in to either) the clunking was always there, so I suspected U joints, but now I'm lost. What do you guys think is wrong?

It grinded when I drove it, park worked at first, and then it started rolling backwards. Emergnecy brake didnt work, and I'm stressed out. No rear end fluid anywhere. Noticed what I think is a hose disconnected to the rear end?

Just before this happened, it started vibrating just after a shift in 2nd or 3rd, going 25-40mph. Tap the gas more, it went away, let off the gas, it went away. Just before it messed up on the way home, it started vibrating even when decelerating (no gas). Still, it went away when I accelerated. (So it only vibrated with LIGHT gas after shift, then started doing it even when braking/slowling down). It also vibrated and made funny noise on the interstate, but not 1/10 as bad. Felt almost like a wheel was off-balance (but just had them balanced).

4wd didn't fix anything it had the same probekms, but made awful grinding noises when taken in/out, and same from drive to reverse.

this sucks anybody have an educated idea?

I know this doesn't help much but you said your e-brake doesn't work and you saw a cable that goes to the rear disconnected. That might be your e-brake cable. Just wanted to let you know.

 

[4FordFamily]

It ended up being the entire rear end, it was ruined (in pieces).

 

[uefear]

Are you referring to the rear diff?

 

[4FordFamily]

Are you referring to the rear diff?

yes.

 

[4FordFamily]

Everything is fixed, it was the rear end (or rear differential) everything works great now.. 850 dollars later