Ok, I have some strange noises eminating from my Dana 300. Hopefully someone can help...

Here are the specs:

Front and rear Dana 60's with 6.17's and 38.5 TSL's
Estimated 10" of lift
Front driveline disengaged
Rear driveshaft ujoint angles close to the same
Rear driveshaft length 37"
Clocked Dana 300
Tcase full of 90 wt to where it runs out of the fill hole.
There is no apparent looseness at either output shaft.

In drive at greater than 2500 RPM's on the street, I get a hellacious buzzing / grinding up out of the shifters on acceleration, decelleration and coast.

At less than 2500 RPM's, I only get the noise on coast or deceleration, but not when accelerating.

I am sure my rear driveshaft is NOT even close to true and not balanced (but it is well used) and my spares are no better.

Any suggestions for what is causing my noise? Is it driveshaft related, or is it likely to be something inside the case?

Wow, what a long rambling post that I am sure will get all kinds of responses......

Thanks in advance.

Ed

I may be wrong, but the D 300 is a transfer case, and therefore does not spin base on rpm, but on tire speed... The D 300 might not be your problem

Mine seems the same, not happy after 2500RPM.
First time I went through this, I found the shifter bolt on the 300 being loose caused most of the noises.

David

Ok, just tested the runout in the straightest driveshaft....

hehe


hehehe


.75"

No I did not miss a zero between the decimal and the 7

I guess that is the cause of my noise, huh?

Ed

That would probably do it :)

David