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| | | | Joined: Sep 2003 Posts: 29 'Bolter | | 'Bolter Joined: Sep 2003 Posts: 29 | My stock 53 AD (216, 3sp) is acting up at about 35-40 mph. In this case I actually can't tell whether it's engine, trans, or further back. Get it up to 40 and it has a low rumble and some vibration. If I back off the accelerator a little, "coasting" at 40mph+, the rumble goes away. Thoughts?
Any simple checks to diagnose?
PM
| | | | | Joined: Jan 2008 Posts: 4,961 'Bolter | | 'Bolter Joined: Jan 2008 Posts: 4,961 | Is it a 1/2 or 3/4 ton. On a half ton the joint behind the transmission can make the noise you describe. On a 3/4 ton with the drive shaft open from the center bearing back, it could be a u joint, could be the center bearing or a loose pinion yoke or pinion bearing. | | | | | Joined: Sep 2003 Posts: 29 'Bolter | | 'Bolter Joined: Sep 2003 Posts: 29 | | | | | | Joined: Jan 2008 Posts: 493 Shop Shark | | Shop Shark Joined: Jan 2008 Posts: 493 | Do you still have the closed drive shaft? Check to see if you can reach a point in second gear that makes the same noise. That at least tell you if it is related to the engine RPM and not the speed. If you have an open drive shaft could be a U-joint. I will pull out the shop manual later to see if it says anything. I will guess it is not a tire since it goes away if you coast at the same speed. | | | | | Joined: Sep 2003 Posts: 29 'Bolter | | 'Bolter Joined: Sep 2003 Posts: 29 | | | | | | Joined: Jan 2008 Posts: 493 Shop Shark | | Shop Shark Joined: Jan 2008 Posts: 493 | I have also isolated a noise by taping a microphone to the parts in question and driving. It helps if you have a stereo recorder and can use 2 mics at the same time. One front and one back or one on the drive housing and one on the rear end. The wind noise is a problem and I just put some tape over the mic so you are just picking up the vibrations. Just a thought. | | | | | Joined: Apr 2008 Posts: 899 'Bolter | | 'Bolter Joined: Apr 2008 Posts: 899 | Have you checked your tranny and rear end oil levels? As noted above the U-joint could also be suspect. Good luck.
Ed
| | | | | Joined: Jan 2008 Posts: 4,961 'Bolter | | 'Bolter Joined: Jan 2008 Posts: 4,961 | I would take a good look at the "wobble joint" behind the transmission and see if it is showing signs of hitting the bell shaped flex joint. | | | | | Joined: Oct 2002 Posts: 4,066 Bolter | | Bolter Joined: Oct 2002 Posts: 4,066 | you stated "back off the accelerator a little, "coasting" at 40mph+, the rumble goes away. Thoughts?
the rumble goes away but what about the vibration.
get it up to 40 and take it out of gear and see what happen.
Redryder pixMy HotrodA veteran - whether active duty, retired, national guard, or reserve - is someone who, at one point in his or her life, wrote a blank check made payable to The 'United States of America', for an amount of "up to and including my life."I am fighting cancer and I am winning the fight | Pain is part of life; misery is an option. | | | | | Joined: Sep 2003 Posts: 29 'Bolter | | 'Bolter Joined: Sep 2003 Posts: 29 | Finally got some time to look at this again - the trans fluid was WAY low. Filled it up, and guess what - all good!
Now to solve the leak(s), which are apparently worse than I thought!
Thanks for all the suggestions.
PM
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