Bronco Forum - Full Size Ford Bronco Forum banner

1 - 20 of 52 Posts

·
Registered
Joined
·
203 Posts
Discussion Starter #1
Ok, I have read a million threads in here regarding road vibration. What I have is an 86 5.0 EFI with a 4 speed manual. My truck has a vibration that is really bad around 65-75 and pretty much goes away after 80. I still can kind of tell it's there, but it settles down big time after 80. Anyway, I have removed my rear drive shaft and just drove with the front differential so that ruled out the rear u-joints and the rear pinion. Then I put in the rear drive shaft and took out the front shaft to rule that out. I checked the front steering and it is a bit worn, but not loose enough to cause such a vibration. The radius arm bushings are fine. The wheels and tires I have replaced (talk about wasting money trying to chase a problem down). The wheel bearings are fine. The engine mounts and trans mounts are new. I checked fluid levels in the front and rear diff, the transfer case and the trans. The trans is old and there was some metal debris in the bottom of the case when I changed the fluid, but it still functions perfectly.

So here is my point. I have searched and read through TONS of vibration threads on this site. I have done my homework. One thing I have noticed is that on all these vibration threads, a bunch of people give great advice and suggestions, but I have not read one single thread where they actually post what solved the problem. So what I would like here is a thread that ONLY contains replies of people who have had vibration issues, and what they did to SOLVE the problem. I just want to create a better vibration thread for this forum, since the ones that are out there do not contain any posts where someone says "I did this and that and the vibration is gone!"

Thanks for reading and I hope to hear back from you guys that have been down the dark road of solving the illusive vibration problems!!!!
 

·
Banned
Joined
·
6,933 Posts
IU thought I posted the solution in a thread I started on that problem with my '89 (302/EFI/AOD).

Bad vibration symptoms: Couldn't accelerate up slight grades in high gear; couldn't use overdrive at all; couldn't accelerate safely in traffic without downshifting to second;...etc.

Problem; Engine lugged badly due to loss of power.

Solution: Rebuilt heads, cleaned TB, general tuneup and problem was solved; runs fine now.

But I don't think this applies to your problem. Does your's only vibrate at 65-70mph and never at lower speeds?
 

·
Registered
Joined
·
621 Posts
rotate and balance the tires. take it somewhere that has a road force machine. you might need tires, andthe shocks could possibly be the cause. if you have tires bigger than a 35, forget about it. the vibration isn't going anwhere. also i would suggest having your driveshaft balanced. mine would vibrate your teeth out of your head. new tires, new shocks and a balanced driveshaft. almost rides like a cadillac. but not quite.
 

·
Registered
Joined
·
203 Posts
Discussion Starter #4
badpony93 said:
rotate and balance the tires. take it somewhere that has a road force machine. you might need tires, andthe shocks could possibly be the cause. if you have tires bigger than a 35, forget about it. the vibration isn't going anwhere. also i would suggest having your driveshaft balanced. mine would vibrate your teeth out of your head. new tires, new shocks and a balanced driveshaft. almost rides like a cadillac. but not quite.
Did you read all my post above? The tires and wheels were just replaced with new and yes they were balanced. I have driven the truck WITHOUT the driveshaft in it, so there is no way it was causing tyhe vibration. All shocks are new.
 

·
Registered
Joined
·
2,331 Posts
check and see if your rear axle shafts slide in/out of the housing 1/2 inch each like mine. It leaves me puzzeled that it didnot go away with the removal of the drive shafts.

if you want, here's my vibration post.
 

·
Registered
Joined
·
1,864 Posts
JustinC said:
Did you read all my post above? The tires and wheels were just replaced with new and yes they were balanced. I have driven the truck WITHOUT the driveshaft in it, so there is no way it was causing tyhe vibration. All shocks are new.
9 times out of 10 when you can "drive out of" a vibration, as you said you can, its a wheel/tire balance issue. I know you said that yours are new, but I dont care.....I would re balance them if I was you. You can also, like another reply said look for a place that has a Hunter DSP or GSP 9000 series balance machine, that will mimic road force on the tire while its rotating......this has been known to solve MANY hard to diagnose vibration problems.

You can locate a place in your area that uses one of these balancers by clicking here.

If you feel the vibration in the steering wheel....chances are better that its a front wheel out of ballance......if felt in the seat of the pants....chances are better its in the rear.
 

·
Registered
Joined
·
5,024 Posts
Streetgang said:
I would re balance them if I was you.

Gang is right...some folks play at balancing, and put on some pretty weights...other folks actually DO BALANCE THEM.

Besides, is a cheap rule out!
 

·
Registered
Joined
·
203 Posts
Discussion Starter #8
Ok, I am going to look for that machine and have them balanced. You know, I do all the work on all my cars and you know why? Because I do it right and EVERY TIME I leave it up to someone else they let me down. Now, you know that we are kind of forced to let other people do a few things like smog tests, alignment and tire mounting and balancing. Why? Because not everyone can afford to own all the machines necessary to do the work.

So I leave ONE SIMPLE THING up to a mechanic, just to balance my god damn wheels and they screw that up. Ok, I am going to take your advice and have them rebalanced. If it turns out to be a balance issue, someone is going to get shot. :twak
 

·
Registered
Joined
·
1,864 Posts
Just dont take it back to the place where you first had them *balanced*.
Find a place that does ONLY wheels and tires.....take a look at their machine....make sure its a newer one.....then and most important....STAY RIGHT THERE and watch the guy doing the job, and make dam sure he is doing it correctly...(I am assuming you know how to work a balance machine here). If they say you cant be in here....or some bullshit like that.....tell them "then you cant balance my tires", and go on to the next place.
 

·
Registered
Joined
·
203 Posts
Discussion Starter #10
I just hope you guys understand that when I say "vibration" I am talking about the door panels shaking violently like they are going to fall off.
 

·
Registered
Joined
·
1,864 Posts
JustinC said:
I just hope you guys understand that when I say "vibration" I am talking about the door panels shaking violently like they are going to fall off.
But you can drive out of this violent vibration.....no, and you said you have eliminated the both drive shafts from the equasion......so I stick by my first response to your question......rebalance the tires.
 

·
Registered
Joined
·
150 Posts
So you're saying that you took out the rear DS and then put it in 4wd and got it up to 75-80 mph to rule out the rear DS?

FYI the front DS doesn't engage unless you have the t-case in fwd, so that didn't need to be removed to rule out the rear DS unless the vibration you're talking about only happens when youre going 75 in fwd.
 

·
Registered
Joined
·
203 Posts
Discussion Starter #13
bent said:
So you're saying that you took out the rear DS and then put it in 4wd and got it up to 75-80 mph to rule out the rear DS?
Yes, and it still vibrates. :banghead

bent said:
FYI the front DS doesn't engage unless you have the t-case in fwd, so that didn't need to be removed to rule out the rear DS unless the vibration you're talking about only happens when youre going 75 in fwd.
Right, but who knows what might be happening when I am rolling on the freeway. Maybe I had a hub that would engage at speed. Maybe the transfer case was stuck in 4WD and I didn't know it. You have to rule out things like that...
 

·
Registered
Joined
·
150 Posts
Do you have a lift on the TTB? Maybe have your alignment checked.

I had a pretty bad vibration a while back. Turned out that a couple of the bolts that mate the transmission to the engine had come loose. it basically shook itself apart and cracked the tranny housing. My symptoms were different though, it would run fine while accellerating, but would shake like hell while decelerating at all speeds. You could visibly see the transfer case stick shift shaking around violently. I think that i had a bad tranny mount, which in turn caused a vibration which lossened the tranny bolts which caused my tranny case to crack.

so if you havn't already, i would reccomend checking out your tranny and motor mounts.

GL :shrug
 

·
Registered
Joined
·
2,331 Posts
JustinC said:
I just hope you guys understand that when I say "vibration" I am talking about the door panels shaking violently like they are going to fall off.
keep in mind that there is a hell of a lot of weight flying around on those tires at 75-80 mph if they arent balenced right, quite enough to shake door panels.
 

·
Registered
Joined
·
203 Posts
Discussion Starter #17
Last night I had to make room in my driveway so I can do some work on some other cars for some side cash. Anyway, I had to tow my boat over to my mom's house so I hooked it up to the bronco and drove it over there. Nice ride at about 60 the whole way, and you couldn't even tell it was towing anything. So after I droped it off, on my way back home I got up to 70 where is shakes the worst. Then I had my girlfriend crawl around into the back of the truck. I wanted to find out if the vibration was coming from the front or back because I can't tell. So she sat up front, then went to the back, then came back up front. She couldn't tell. It was like it was coming from everywhere. I put my hand on the shift lever while it was shaking and it didn't feel like the trans was causing anything or attached to anything that was causing the shaking.

I want to think I can just replace a trans or engine mounts or resurface the flywheel, but if the vibration was coming from the motor, wouldn't the stick shifter be all over the place when it's vibrating? Today I am going to go home and jack up the rear end and pull off the rear tires to see if something is wrong with the rear wheel bearings......

Some day, after I have rebuilt the whole damn truck, I will find out what is causing this.
 

·
Registered
Joined
·
1,864 Posts
Did you have your tires rebalanced yet????
 

·
Registered
Joined
·
124 Posts
Have you checked to see if the rotor hub was square? If the lugs are not tightened in the correct sequence/torque spec, it could cause the rotor hub face itself to become warped and cause a vibration much like a tire imbalance. I am in no means doubting your work, just trying to make suggestions. Good luck

Nick
 
1 - 20 of 52 Posts
Top