Engine/Transmission/Rear Differential Noise Detector Finder Tool

[Gerald C.]

I'm trying to determine where a "humming" sound is coming from in the drivetrain of my 63. The humming occurs upon acceleration and stops upon deceleration. Before I start dismantling either the 4 speed tranny or the 3:36 non-posi-rear end, I'm trying to do as much research as possible. One recommendation I received is to purchase one of these tools and hook it up to both the tranny and rear differential and drive the car so the drivetrain under "load". Has anyone used this noise finder tool on their c2's with any precision and or luck or have any other suggestions? If you have purchased one, can you share the tool information that you used?

Thanks

[Mark E.]

If no response here ask a car dealer or mechanic. I haven't used one but our local Jag Land Rover dealer has. I believe they strap to the chassis and bluetooth connect to an app on a phone.

[David M.]

Is this a fully restored car, survivor car, low mile car? How many miles on the drive train?
Do you have any drive-train service history? Has the trans, diff, u-joints, trailing arms ever been serviced?

Take a passenger for a ride-along as they will be able to poke their head behind the seats to give you some indication of the sounds origin.

Noise on acceleration is generally u-joint, engine, or trans mount.
Look at the main drive shaft for witness marks indicating contact with something.

Split the dictionary:
Start simple. As you go deeper the following parts will need to be removed anyway...
Pull the main driveshaft and run the engine gently through the gears. Low RPM nothing above 1500.
Sound gone? Its likely the drive shaft or the rear suspension. If its not gone its likely the trans or clutch.

Dont rule out a bad U-Joint. Manipulate the main & half shaft U-joints as you remove them, they should be smooth.
You can visually see a sloppy failing cup and cross shaft. The rust dust is a dead giveaway.
You do not need to remove the shafts to see these defects.

With the driveshaft out check the pinion radial and axial slop.

Next pull the half shafts, check u joints then check for bearing slop at the diff flanges then at the trailing arm flanges. There will be some lash but shouldn't be excessive.

Spin the components by hand to feel for bearing brinelling.

A fancy tool isn't any better than good old fashion spatial awareness... touch-see-hear-smell.

Trailing arm bearings notoriously fail at 40-60K miles. Especially if they've been in situ for the last 62 years and never been greased...if 63s can be greased? But they will make noise all the time so you may rule this out.

My money, sight unseen, is on u-joints or mounts.