that's how my transmission Guy found my first bent driver side axle, I found the second one running it on my lift...
ive watched many a vehicle going down the road with a bent axle. happens more than you think I bent one on my 03 Dakota r/t in Chicago, I slid into the side of a curb, didn't hurt the rim but bent the axle. worth checking.
.030 to me is too much... there is a seal there also. you really need the driveshaft installed to check this right. there is a running depth that it needs to be at to check it.
Before I did anything, I'd run the engine at steady RPMs in the 3000-3500 range to see if any vibration is detectable, if it's there you have a converter or engine issue...
A driveline vibe and a tire/wheel vibe are two VERY different sensations. The driveline is spinning (in the OP's case) 4 times as fast as the tires are. That's why the vibe got noticed after the gear change. Mine had a vibe too in the driveline, but it went away after the Toploader replaced the C4. The C4 apparently had a bent mainshaft. A driveline vibe is a high pitched buzzing, a tire/wheel vibe is more like a "whole lotta shakin goin on". If it is the driveline, now's a good time to upgrade that with a newer shaft outta a 2000-2004 Stang.
Sorry it took so long for me to get back on here. I got the drive shaft back and installed it, he said it was off a good bit, had to remove 3 of the weights that were welded on, now its good to go. I still have to replace the rear seal but I went for a drive last night and for the fix 5 so miles up to 60 mph was smooth. Then I went to head home pulled in a neighborhood and turned around got back on the hwy home and noticed getting up to speed that now at 2400 rpm had really bad vibration and it gets less but quicker in frequency up to 60 mph. not sure if a u joint shifted or something got to look at it today. it was fine then came back just little different than before. I don't think I really described the vibration before, you can feel it in the seat right in the lower back. not the steering wheel or dash but in the floor about right at the rear of the trans right where the seats are mounted. Its a rotational come and go kind of, like it peaks and lessens like every couple seconds and gets faster as the rpms climb but goes away when i let off the gas for the most part and if i put in neutral goes away if i rev to 3000-3500 its not there either. I'm going to look at the u joints this weekend and try again if no change im going to check the pinion angles. i have 4 leaf rear springs and lowering blocks.
Are you now describing a different vibration from your original post or is it just in more detail? The vibration you are now describing I would have thought you would have noticed before your installation of the 4:11 gears? In my experience a vibration going away in neutral pretty much eliminates wheels, tires and axles. Pinion angle tends to come into play during moderate to heavy acceleration/deceleration. Is there any moan associated with this vibration? Personally, I suspect your new ring and pinion because I don't know how you could have missed the vibration described above prior to their installation. Ring and pinion Noise Vibration and Harshness (NVH) tends to disappear when you put the car in neutral and also tends to come and go during a road test. What is the detailed history on your new ring and pinion installation? Is it used pumpkin, rebuilt pumpkin from a reputable rebuilder using a new ring and pinion, or just a ring and pinion install and by whom? Regardless, I have attached a link that has a huge amount of information on NVH diagnosis. Pay particular attention to the Road Test Quick Checks almost at the bottom of the site. http://www.thedieselstop.com/faq/9497faq/maint/stj/stj04003.htm Unfortunately this site may totally overwhelm you!!! Utilizing a set of "Chassis Ears" is the fastest way to diagnose NVH.
This is just more details on the vibration I have. Before the 4.11s so many other things were being replaced ( bushings, mounts, suspension wheels and tires brakes) over a year or so there was always so many vibrations couldnt tell if this was involved. I rebuilt the rear axle all the bearings and installed 4.11s and a mini spool. I didnt have anything strong enough to crush the crush bearing on the pinion, took it too a local shop and they did it for me and double checked all the specs and said it was good to go. installed it and thats when i got the vibration. Not sure why it was fine for a couple miles and came back, was nice and smooth then turned around and came back at a lower rpm and still there just a faster frequency at highway speeds. There is a moan i guess you could say when it is happening, like a wan wan wan wan wan ( if you know what i mean)
the only thing ive ever encountered in a differential to cause a vibration is if the pinion bearing preload is loose. if you can wiggle the yoke with any perceivable movement then you dont have your pinion bearing preload correct. careful not to mistake the back lash rotation amount as a wiggle motion. ive had a c4 tha caused a drive shaft vibration. i assume it was a bent output shaft but never verified it. i swapped to a t5 and it was smooth as can be after that.
If it's coming and going as you say, you've got something loose somewhere. And when it comes completely loose, you'll know then what it is, and it ain't gonna be pretty when it identifies itself. I also have a hard time believing the balance that shop did. There was a reason those weights were put there in the first place. And it wasn't to throw the balance off.
there is no wiggle in the pinion and i have checked everything for something loose and nothing seems to be. I think the thing with the weights maybe someone who owned the car before me changed u joints and swapped ends with the yoke, maybe dont know for sure but that may of been why they were there and now are not needed. all i do know is they vibration went away and then came back.
Not sure why it was fine for a couple miles and came back, was nice and smooth then turned around and came back at a lower rpm and still there just a faster frequency at highway speeds. sam03rc, I'm not exactly sure what you are stating here? Are you saying the car ran fine then you turned around and it started vibrating and making the wan, wan, wan moan again?
yes ran nice and smooth, turned into a neighborhood and turned around and then the vibration came back almost the same just a little lower in the rpm band and faster when i got up to 60.
