Squeaking when accelerating vibration when slowing down

[Alex8706]

92 explorer sport 4x4 5 speed manual with manual locking hubs.

Ive been having some squeaking going on at pretty much all speeds for a few weeks now but havent done anything about it. But this morning i started to get some vibrations while slowing down starting at about 35-40 mph. The closer i come to a stop the more extreme the vibration is and i still get the vibration when i coast to a stop too just not as extreme. Brake pedal doesnt vibrate at all. Steering wheel doesnt seem to move. Thought it might be a warped rotor, and maybe it is, but i thought those were two signs of that. I dont know a lot about suspension but i did get under it to check to see if anything was loose but it all felt good.

I did replace the rear drum brakes and hardware about two months ago. Havent done anything to the front. Recently learned that i can go forward and reverse and sharply brake to adjust the back brakes better and i did that about a week ago. I am confident i put all the hardware on properly. Not sure if that can be a casue or not but figured it might be worth mentioning.

Not sure what it could be. If i could get any ideas that would be great. Thank you.

 

[cooksmtn]

Check your U-joints. Dry ones can squeak, and loose ones can cause the type vibration you mention.

 

[Alex8706]

Check your U-joints. Dry ones can squeak, and loose ones can cause the type vibration you mention.

Do you mind explaining to me how to properly check them?

 

[cooksmtn]

Set your parking brake, trans in neutral. Crawl underneath, grab each end of the driveshaft, and try to move it, rotationally and up and down / sideways. Should be NO movement.

 

[Alex8706]

Set your parking brake, trans in neutral. Crawl underneath, grab each end of the driveshaft, and try to move it, rotationally and up and down / sideways. Should be NO movement.

All four of them seem tight. It's kinda hard to get to the ones behind the front hubs but I didn't see or feel any significant movement.

 

[cooksmtn]

OK you're probably going to have to separate the squeaking from the vibration. Vibration can be bent wheel, loose wheel (make sure your lug nuts are tight, since you say you did rear brakes), out of round tire, out of balance tire, flat spot on tire, bad tire, loose front wheel bearings, loose rear axle pinion. Did the problem start after your brake work? Warped rotor usually shows up as pulsation in brake pedal. Loose pinion vibration usually shows up in the floating/coasting stage between acceleration/deceleration. And you might see an oil leak at the seal. Eliminate any front drive train by having it in 2wd, nothing up front turning (hubs unlocked). Try to notice if it is worse or better when going around turns and at different speeds. The more you can narrow down the conditions under which it appears, the more likely you are to find it.

Good luck.

 

[Alex8706]

OK you're probably going to have to separate the squeaking from the vibration. Vibration can be bent wheel, loose wheel (make sure your lug nuts are tight, since you say you did rear brakes), out of round tire, out of balance tire, flat spot on tire, bad tire, loose front wheel bearings, loose rear axle pinion. Did the problem start after your brake work? Warped rotor usually shows up as pulsation in brake pedal. Loose pinion vibration usually shows up in the floating/coasting stage between acceleration/deceleration. And you might see an oil leak at the seal. Eliminate any front drive train by having it in 2wd, nothing up front turning (hubs unlocked). Try to notice if it is worse or better when going around turns and at different speeds. The more you can narrow down the conditions under which it appears, the more likely you are to find it.

Good luck.

Thanks for the tips. There definitely wasn't any squeaking or vibration before I changed the drum brakes and it didn't start until a handful of weeks after I did them. It will take me a few days to narrow it down more but when I do I'll post what I've came up with.

Thanks for the help and suggestions cooksmtn.

 

[Gary Crist]

Also, when checking u-joints, look for what looks like rust coming out of the joint. That is the
worn out steel from the cup and bearings.

 

[2stroke]

The first thing to do is determine if the sound relates to engine speed, or vehicle speed. You can put it in neutral and coast, if the sound stays the same, it is speed related. If it slows or stops, its the engine. The next is to eliminate the front end. I would jack up the front wheels and check for play. It wouldn't be impossible for this to be a bad wheel bearing. If everything is tight, then it's most likely in the rear. If you have manual lock hubs, make sure they are unlocked. If auto hubs, while the tire is jacked up, make sure you can spin it freely without the axle shaft turning. After that, I'd really be suspicious of the U joints. There is a single joint at the axle, and a double cardan (2 U-joints with a ball) at the transfer case. I've found it can sometimes be necessary to jack up the vehicle by the frame, with jack stands of course, and check again. It may be just as easy, and safer to just take the driveshaft off. Grease the slip yoke while you are at it.

 

[Alex8706]

Ok so ive been able to check it out a little more. Rear end tires, drums and hardware look good. I wasnt able to raise the back end up fully, because i dont have stands or a proper jack so i had to do one tire at a time, but i noticed when i rotated the tires back and forth there wasnt any noise. Did the same with the fronts took the tires off, inspected everything and everything seemed tight and as it should with the locking caps engaged and disengaged.

As far as the vibration goes, i am noticing while driving it that it is speed related. I can hear it, if that makes sense, before i start to feel it. You can hear it best and feel it most when going from high speeds to a stop. Usually i hear it at about 40mph and start to feel it at about 20-25mph. It hasnt been as bad as it was when i first posted but its still there.

Now i bought this explorer back in October and i havent used the 4x4 at all ive just kept it in rear 2wd. So if it is the u joints id be safe to say that its one of the rear ones i am guessing. I did recheck the rear driveshaft and there was play. I must of been oblivious to it before when i checked.. What i did which is what was suggested earlier and grabbed onto each side of the u joints and gave it a real good twist. There was most definitely play where the boot was (1st pic) in the middle of the shaft. There seemed to be play with the u joint near the transmission (2nd pic). The u joint near the rear seemed to be nice a tight (3rd pic). I couldnt feel any play trying to move the driveshaft up, down, left or right. I took and upload pics of the joints for the hell of it maybe you guys will notice something i cant.

Now the noticeable looseness at the boot in the middle of the driveshaft is a u joint or is it something else? I ask because of the boot and why they would put that on there and not on the other ones. The transmission joint seemed loose but it was hard for me to tell. But if whatever is in that boot is suppose to be tight than im guessing thats my issue.

EDIT: This might be unrelated but ive noticed its been a little more difficult for me to get into low gears lately and ive also been getting some grinding going into first and into reverse. Would this be related since its the transmission driveshaft u joint or am i just having transmission issues also?

 

[Roadrunner777]

Whatever this ends up being, there's one thing I noticed: The rubber boot still has the factory metal bands on it, so most likely, the slip joint hasn't been lubricated in a really long time.

 

[2stroke]

That boot is what covers your slip yoke. It is splines that go together with female splines so that as your suspension moves, the driveshaft can expand or contract. The splines are supposed to have a blue teflon coating, and be greased periodically beyond that. If it's been neglected for 25 years, I'd guess that Teflon coating can be worn down. I don't think I've ever noticed play from one, so something may be wrong. Are those 2 pictures of the axle side u-joint, or do you only have a single u-joint at the transfer case? If you found play at one of the transfer case side u-joints, that's the place to start.

 

[Alex8706]

That boot is what covers your slip yoke. It is splines that go together with female splines so that as your suspension moves, the driveshaft can expand or contract. The splines are supposed to have a blue teflon coating, and be greased periodically beyond that. If it's been neglected for 25 years, I'd guess that Teflon coating can be worn down. I don't think I've ever noticed play from one, so something may be wrong. Are those 2 pictures of the axle side u-joint, or do you only have a single u-joint at the transfer case? If you found play at one of the transfer case side u-joints, that's the place to start.

The two u joint pictures i took were from the driveshaft at the transmission and the driveshaft at the rear axle. According to this picture. The u joints from the transfer case to the front all seemed good. Its in rear wheel drive all the time so i figured the u joints for the front were not the issue. I am pretty sure this picture is accurate to my vehicle. I cant go check right now though.