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Discussion Starter #1
I'll start by saying i'm new to diesels.

If I got my foot into it, with boost pressure at 18 or so and at 60-70mph. The truck will start shacking. Is there something wrong or is this supposed to happen, like boost pressure to high or something. i do have the bullydog program on performance

Thanks
 

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18 is not high. shaking or vibrating? Shaking to me sounds like tires and drivline bad. when the TC locks and your pouring power to it mine kinda vibrate as it putting torque to the wheels. A bit more info may be needed to help ya out.

Oh and Welcome to the diesel world. I see your a fellow Canadian. I grew up in abbotsford.
 

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might be transfer case as well. i have had that happen to me
 

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Discussion Starter #4 (Edited)
The tc locks up at around 55 and if I put the the foot down it accelerates great up to 70-75mph and the boost pressure gets to about 18 maybe 20 and then it starts vibrating. I can accelerate to that speed with no vibration with the boost pressure lower. It only seems to be when the boost is up there. What would be high boost pressure?
 

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mine gets to 42 lbs, without a fooler they hit 32-36 or so
 

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Discussion Starter #6
I put it in tow/hawl mode and put the power to it at 40mph and the boost got to 26 no problem but started to run out of road so I let off.. it was smooth.. when I got on the freeway I accelerated to 80 mph normally didn't have my foot on it to hard and it was smooth. slowed down to 55mph and rolled on the throttle when the tc locked up I took off and again when the boost got to 18-20 at about 75mph it started, I would call it a mild shudering maybe "i'm not good at explaining these things" . As soon as it does that I let off the throttle, so I don't know if it will smooth out or blow up LOL. Any othwer ideas what it might be
 

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Put the truck in neutral and see if any of your U-joints are wiggling. If they move at all they're bad
 

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Discussion Starter #9
I also noticed today when I got on the hyw it was vibrating and it seemed to go away after awhile. The u-joints seem tight. I got the tire balance checked. What else do you guys think it might be. Is there another way of checking the u-joints I tried this way
Put the truck in neutral and see if any of your U-joints are wiggling. If they move at all they're bad
 

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Could be a death wobble. Though I have never heard of it going away after a while, I have only heard of it going away after you slow down.
 

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I would think it's the u-joints also.
When you are in your driveway or wherever, put your truck in neutral, then from a standstill put it in reverse or drive without touching the brake.

When my u-joint went it made a loud pop when did this.
 

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I know is sounds crazy, but I had the same issue. I tried having the tires rebalance and rotated. I had the dealership insepct and try to figure it out. I got fed-up and solved the problem myself. the U-bolts on the rear axle were loose. I tightened them with my 3/4 drive impact, and BAM no more shake. I hope this helps. I'm here to tell you that the right one turn and full 4 turns and the left about he same.
 

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Discussion Starter #13
Thanks for the replies I will try doing those 2 things in the morning. I don't think it's the u-bolts as it doesn't seem consistant but it wouldn't hurt to check.
 

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just because the u-joints seem tight does not mean they are'nt bad. my rear was bad & also tight, but the problem was that it was dry. it's usually a u-joint but it might be a bad tire also (shifted belt), put in reverse with window down & see if you hear a screaching noise if so it's a u-joint.
 

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I just recently had the same prob sounds like. Everything seems fine until I would reach about 70, then hellofa vibration, could feel it in the steering wheel. Could not find any thing loose from general inspection. I took the front drive shaft out and the cv joint on the t-case end was not loose but tight and was not articulating freely like it was supposed to. Took the shaft to my local drive shaft man. He had the joints and flange in stock. Had it fixed in one day and less than 300bucks. (If u keep running it it gets more expensive, cutting end off shaft and welding new yoke) I would definately think it would be worth th trouble to check the shafts off the truck. If all joints don't move freely in both directions they need attention. Also not a bad idea to grease the splines while u got the shaft out. This will helpt that PING PING we all hear while creepin in 4wheel.
 

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Discussion Starter #16
well I'm hearing what seems like a slight knocking sound as I'm slowing down to a stop ( 5mph ) coming from under the cab slightly forward. It seems to be in rithum with speed not rpm. also heard a slight squeek when backing up. I think it's a u-joint???? If thats the case everything is closed until tuesday ( easter weekend ) I figure I will need to do about 60 miles of driving this weekend. Is this going to be ok is there anything I can do to help it out. Or should I be finding another form of transportation
 

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New here and leaving tomorrow with my son???Maybe!!!! My truck has 47,000 on the clock....Bad universal at rear diff. how do I get drive shaft out??? Already taken off of diff but how do I pull out of rubber boot??? Thanks....
 

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Sounds exactly like a u-joint is going bad. I have the same thing happening to me when I get on it but it starts once I hit 45-50. If I let off the gas for a second then cruise at the speed, it becomes barely noticeable. I suggest you do a test, get on it on a highway and once it starts vibrating then take your foot completely off the pedal for a second then get back on it and keep the same speed, it should go away.
 

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How do you change them??? I'm fighting right now.
 

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death wobble

i get the "death wobble" too, i got the "death wobble" the first time at 80mph and it pitched me sideways...scared the ...heck... out of me, the next time i was in texas and again at 80mph with a few passengers and they all swore up and down that it was a flat, no one rode home with me after that, i then replaced the steering stabilizer and just recently at 50mph it did it again, i've done some research and so far all I have seen is the track bar is infamous on dodges especially for going out. and it looks like so far the cheapest is $200 +/-. i have seen a few adjustable bars for up in the $400 range as well. unless someone can tell me what else could cause this.
 
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