Thoughts on shudder???
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From: Isanti, MN
U-joints can be tricky, though. I've seen them bind without having any visible play, which is possible for the OP because it's not yet vibrating at speed. The most comprehensive way to check them out involves removing the shaft, which is a fairly easy thing to do.
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From: Isanti, MN
In theory you should remove 4 ounces, but I just jacked up the left rear wheel to prevent spillage and poured it in.
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So i added the friction modifier, took it for a drive a few miles away, did a lot if figure 8 turns in a parking lot, then drove back home. I didn't notice any change yet. But im definitely going to bring the truck back and have them check it out. I don't care if i have them replace all 3 ujoints just to do it.
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From: Home Base Nebraska
So i added the friction modifier, took it for a drive a few miles away, did a lot if figure 8 turns in a parking lot, then drove back home. I didn't notice any change yet. But im definitely going to bring the truck back and have them check it out. I don't care if i have them replace all 3 ujoints just to do it.
Denny
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So i was looking over my repair bill, and i noticed that they put 75W90 in the rear instead of 75W140. The owners manual recommends the 140. And seeing as i tow a 37' fifth wheel, i am thinking i want them to drain and refill with the 140. And the owners manual also calls for 8 oz of friction modifier. I finally found where it was listed.
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Joined: May 2004
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From: Home Base Nebraska
So i was looking over my repair bill, and i noticed that they put 75W90 in the rear instead of 75W140. The owners manual recommends the 140. And seeing as i tow a 37' fifth wheel, i am thinking i want them to drain and refill with the 140. And the owners manual also calls for 8 oz of friction modifier. I finally found where it was listed.
Denny
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Joined: Nov 2011
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From: Land of Taxes
Looks like its hopping around in the first vid.
Like I said push up/down at the pinion end to see if you have movement. Some deflection on the xfer case tail shaft is normal.
I'd pull the shaft and articulate the ujoints to "feel" them. Feel the slip joint too, in-out & up-down.
Take it to a shaft shop and have them inspect and balance. Spicer Ujoints and carriers are the only ones I will use.
Be sure to mark the yokes and shaft before removal.
Clean both yoke surfaces & apply a thin coat of anti-seize between them.
Clean the bolts and the bolt holes with brake cleaner, apply blue 242 Loctite and re-torque.
Like I said push up/down at the pinion end to see if you have movement. Some deflection on the xfer case tail shaft is normal.
I'd pull the shaft and articulate the ujoints to "feel" them. Feel the slip joint too, in-out & up-down.
Take it to a shaft shop and have them inspect and balance. Spicer Ujoints and carriers are the only ones I will use.
Be sure to mark the yokes and shaft before removal.
Clean both yoke surfaces & apply a thin coat of anti-seize between them.
Clean the bolts and the bolt holes with brake cleaner, apply blue 242 Loctite and re-torque.
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Update!
Not only drain and refill but pull the axles and flush it out completely. When I had my 2000 F350 it had a pinion seal leak still under warranty and I put some 75W90 in it and too get home but when I took it to the dealer where a good friend worked on it and I told him that what I did he recommended flushing it and after I told him to fix it like it was his he flushed it.
Denny
Denny
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Kind of looks like a u joint sound would have been nice in the video. You can chock the wheels, put the truck in N and use a large drift, pry bar or flat head to check for play. I recently replaced my rear most u joint and have a new one ordered for the front of the rear shaft. It is a pretty tight tolerance I have about .5 mm maybe less of play and it causes a disturbance when driving at certain speeds.
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Elder User
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Kind of looks like a u joint sound would have been nice in the video. You can chock the wheels, put the truck in N and use a large drift, pry bar or flat head to check for play. I recently replaced my rear most u joint and have a new one ordered for the front of the rear shaft. It is a pretty tight tolerance I have about .5 mm maybe less of play and it causes a disturbance when driving at certain speeds.
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Elder User
Joined: May 2007
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Kind of looks like a u joint sound would have been nice in the video. You can chock the wheels, put the truck in N and use a large drift, pry bar or flat head to check for play. I recently replaced my rear most u joint and have a new one ordered for the front of the rear shaft. It is a pretty tight tolerance I have about .5 mm maybe less of play and it causes a disturbance when driving at certain speeds.
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From: Isanti, MN
I'll try to upload another video i took yesterday. I jacked it back up to look at it more. I could really see the driveshaft vibration at the carrier bearing. But one thing I noticed, was that with the tires off the ground and the truck in neutral. I had a real hard time spinning the tires by hand. The driver side wheel i couldn't rotate at all, and the passenger side was really hard to rotate. Does that mean anything?
The clutch packs are always under load, which will offer resistance when trying to spin them by hand. An open differential has a completely different feel without this resistance.I spent a lot of time chasing my tail with driveshaft vibrations on a couple different vehicles, and I was never able to correlate visual oscillation like you see in your videos with the problem. I even had a few driveshaft replaced because I could see a slight wobble, and the shiny new ones had a similar wobble. If you not getting a vibration at speed, look elsewhere. Your U–joint could be binding and not cause an out-of-balance condition that will be visible while spinning.