Transmission

[Matto]

I either glide in gear or let off the gas in gear there is a loud sound that is not quite a grinding sound, but it does not sound "right."

Just throwing out another idea, on my 54 3B F head, if the timing is slightly retarded, you can get a very subtle and rapid backfire thru the exhaust when you let off the gas and coast. It almost sounds like something rattling.
Matt
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[macrisel]

Also make sure the yoke's are aligned on the drive shafts. If they are not aligned it can cause a low rumbling sort of vibration..Probably not the source in this case but you never know...

?

Were the rear U-joints in phase?

I think I know the answer, but I'll ask anyway to be the scapegoat for silly questions, but..........what do you mean about the yoke's being aligned (or "in phase") on the drive shaft?  I am assuming this means that if the front yoke is pointed straight up and down (ie 12 o'clock and 6 o'clock) the back yoke on the rear end should be pointed the same direction upon assembly.

Does this apply to the front drive shaft also?

[F Bill]

The two yokes on the shaft should be pointed the same way. So, if we went from the parking brake hub to the rear axle, the first joint you would set at vertical. The yoke attached to that, and the driveshaft, would be horizontal...the next set of cups would also be horizontal, then the final set attached to the diff would be vertical. The only way to alter this is to slide the driveshaft splines apart and slip it back together offset from where it should be. If you go 90 degrees out it will shake , as well as any other permutation that is not in line.

Some driveshafts only go together one way and on those you cannot get it wrong unless you break something or cut and weld. This applies to both front and rear shafts.

Here's a great Google find on driveshafts worth reading.
http://jniolon.clubfte.com/drivelinephasing/drivelinephasing.html

[Paddy]

Not sure what you mean when you ask "were the rear u-joints in phase?"  I don't know what "in phase" means.

[Paddy]

OK I understand now what in phase means.  I'll check that.  It's possible since I didn't know that I re-connected the propeller shafts incorrectly.  You know what they say about learning something new everyday.

[Paddy]

Alright I checked the phase of my propeller shafts and here's what I found and now a new question.

Each shaft is in-phase with itself.

However, when the first front shaft connecting to the front differential and it's counterpart connecting to the transfer case is at 1 o'clock and 7 o'clock  the  rear front shaft is at 10' o'clock and 4 o'clock where it connects to the e-brake housing and rear deferential.

When the front first shaft of the u-joint is at 1 & 7 on the dial should the rear first shaft and it's counterpart that connects to the rear differential also be pointing at 1 & 7 on the dial?

[Paddy]

One last shot at the above question that is not too clear.

Should the front propeller shaft and its u-joints be exactly parallel and in phase with the rear propeller shaft and its u-joints?

So that hypothetically, should I have four (4) joints on my two propeller shafts pointing at 12 o'clock and 6 o'clock and four (4) joints pointing at 3 o'clock and 9 o'clock?

Thanks

[F Bill]

If it were full time four wheel drive that might be a good idea but you have to disengage your transfer case front shaft to be in 2WD. Unless there is only one possible point for it to engage your matched shafts will probably no longer be matched the first time you disengage and reengage your front axle.

[1955CJ-5]

This thread just came to mind...

http://www.cj3apage.com/cgi-bin/yabb2/YaBB.pl?num=1374991505

Long shot but you never know....

[Paddy]

I was out driving the 3A tonight and here's my new theory.  For whatever reason when I "attempt" to disengage the 4 wheel drive it does not fully disengage, and hence the whine.  Why else would the noise be completely eliminated when I fully engage the 4 wheel drive?  Any thoughts on that theory and if so any suggestions on how to address or determine if that theory is correct?  Thanks,

[1955CJ-5]

Since you don't have lock-out hubs you could take the front drive shaft off to disengage the front axle and relieve the load on the T/C....but if it is inside the transfer case that may not make any difference...

If you were not fully disengaged and you are driving on asphalt you would almost certainly hear other noises, and you would feel it...

[ZekeD]

My ex-wife had phases......I didnt know that U-joints did too.

Could you explain for a doofus?

Zeke (in Oregon)

Sorry.....just read the excellent explanations above.

[Carls_jeep]

Paddy, how do you know if your 4whl lever is engaging or disengaging 4whl drive?

The only way I can think to test that is to jack up one front wheel and put the lever in 2whl drive. The wheel should turn. Put the lever in 4whl drive and the wheel should not turn. If you have lockout hubs they need to be locked to do the test.

Driving it on the road to test is not a reliable way to do that.

I still think your just hearing gear whine and rumble from worn gears. I wish a fellow CJ2 or 3 owner could drive or ride and listen to it.

[1955CJ-5]

When you jack up one end of the jeep only turn the road wheel BY HAND....

Do not start it !!! Ouch!

[RedWilly]

With the TC in 4 wheel drive with all 4 tires on the ground you will not be able to turn the front drive shaft by hand. In 2 wheel drive you will be able to turn the front drive shaft. In neutral you will be able to turn both drive shafts.