Dana 300, 4:1, doubler, Noisy

[smashmetal]

I currently have a toyota to Dana 300 doubler with JB Con. 4:1 in the 300.

I know that doublers have a tendancy to be a bit noisy when driving a road speeds, 25-55 MPH.

Question? are 4:1's going to make the noise level a bit higher?
Seams like im getting alot Tcase noise when im driving around.

 

[kowe69]

The LoMax gears have helical cut teeth that are designed to reduce gear noise. Plus the noise should also be less audible when in high range. If you are hear noise while both cases are in high range, try switch them to low range to see if the noise changes. If not the noise could be from the transmission (especially it it is manual) or more likely the front or rear ring and pinion gears. If the noise only happenes while in a particular transmission gear it may be the trans. If it always happens at a particular speed regardless of the gear it may be a ring and pinion gear. Hope this helps.

 

[smashmetal]

The noise or vibes go's away when I pull the tranny in nutural and coast. I know a bit of it is comming from the rear drive shaft. I took the cheap rout and opted to not have it balanced. But it is mucher better now that it has a CV in it. I was planning to make more of a trail rig but it actually is quit nice to drive around. With the way things are these days it's kinda usless having a rig in the driveway I can't drive to work once and a while.
What are the chances that the 4:1's in the dana 300 could make noise if the tolorances aren't quit right?

 

[kowe69]

The tolorances in the 300 are not adjustable. It is unlikely that could be an issue. It is possible that your rear ring and pinion have worn and developed excessive backlash. This will create a whine noise that is speed and load sensative. It can change as you let on and off the gas. It can be difficult to pinpiont the origin of the noise while in the drivers seat. Try having someone else drive and listen from the back seat or have someone else listen as you drive.

 

[smashmetal]

There where shimes I had to check and replace on either the input or outputs of the 300 when I did the gears though.
The rear end I think is become the pinpoint area though. When I take off there is some definite slop before power is applied to the rear tires. As well as when I stop (engine off), put it in gear and let the brake off. It roles about 4"s before it completly holds it's self.

Maybe the prevoise axle owner put regular 4:56's in a 3:73 carrier instead of the fat 4:56 gears.