Noisey new diff

[MilesnMiles]

Not the locker, but the new ring and pinion. Everything is new in the diff so i cant blame the whine i'm getting on the pinion bearing.
The obvious answer is that it is not correctly set up, but reading a lot on US sites there is a suggestion that some gear sets are just noisey.

It whines particularly on the overrun around 2300 to 1500rpm. Not so bad up round 70-80mph

My real question is;
Will it break or can i drive/race it?currently running in at 3000rpm ish.

[mopar_mark]

Not the locker, but the new ring and pinion. Everything is new in the diff so i cant blame the whine i'm getting on the pinion bearing.
The obvious answer is that it is not correctly set up, but reading a lot on US sites there is a suggestion that some gear sets are just noisey.

It whines particularly on the overrun around 2300 to 1500rpm. Not so bad up round 70-80mph

My real question is;
Will it break or can i drive/race it?currently running in at 3000rpm ish.

I would have concerns if I had laid out hard earned cash on a new Ring & Pinion & it was making bad noises.
Will it break, I guess it depends on the severity. ... Not something I would recommend driving to find out.

I personally would pull the diff assy, clean it thoroughly & lightly grease the crown wheel & see how they both matched. Is it running high/low etc, I would also be looking to check the backlash, too hard a contact causes friction/heat/high wear,etc too much backlash has numerous issues as well.

[Anonymous]

Did you break it in? , around 500 miles of easy driving? maybe not.

[Anonymous]

I had a new LSD, and 355 gears installed by hausers a while back and run them in as instructed. They whined a lot for ages, more noticeable when letting off the throttle (probably cause you can hear more)

Its only been recently that Ive noticed the whine has gone.

[MilesnMiles]

Well, thats interesting. I am running them in for 50 mile at 3000rpm as instructed. Had a couple of very short blats up to 4k, but nothing sustained. Maybe i'll carry on as my description seems very similar to phils, I hope.

[Steve Chapman]

Interesting reading Miles, where did you locate and ship yours, have been on the Richmond site and they say contact local suppliers!!!. How much did the unit cost altogether as i am as tight as you by the sounds of it. Do you have Yorkshire ancestry.

[challenger]

2 days ago i had fitted a set of MOTIVE 3.73,s to my axle with full bearing kit etc, all is well apart from the same as phils motor it whines (not to bad) at 50 mph and slower but not really above that speed, so only really when you come off the throttle on the over run, i double checked the pitch on the gears and it looked fine, have done around 100 mile so far and maybe a tad better, just debating whether to get it stripped back down or run for longer and see how it goes

[MilesnMiles]

well, that's three of us!
I'm running below 3000revs but thats nearly70mph and it whines. Definately much worse on the overrun.
sounds the same as a diff i had second hand that had a failing pinion bearing, except my current diff has all new bearings. strange and annoying.

[ANTON]

read this it may help.Noise on deceleration can be from incorrect pinion bearing preload.






http://www.ringpinion.com/ContentFrame. ... art_1).inc

[MilesnMiles]

Thanks Anton. Looks like a preload issue. On the US site i was told by two diferent people that they had Motive Gear ring and pinions that always whined regardless of how well set up. I have Motive Gear parts.

[Dave-R]

You will always get some gear noise because all gears "whine" as they spin.
How much they whine is down to;
How well they are made.
How well they are set up.
How low a gear they are.

The lower the gear - the more teeth they have and the more noise they make.

So if you switch to lower gears you will always notice an increase in the gear noise.

Personally I would never trust any one else's work. No matter how skilled they are. People are humans and humans make mistakes.

[MilesnMiles]

Dave, i agree about the human error bit. I simply dont have the kit and experience for the black art of rebuilding.

The guy that did it told me that he'd followed all instructions and correct settings.

Overall, the noise offends me, but I really need to know if damage is occurring. Reckon i'll phone Hausers for an opinion.

For those that asked -prices
3.55 ring and pinion $209
Richmond Powertrax Locker, close to $300 plus shipping and taxes
Bearing kit and all assembly parts approx. £110 from Hauser
In total, it aint cheap. Its $1000 for a complete diff with suregrip plus shipping and taxes from US suppliers.

[Pete]

I think you tend to get a resonant frequency so a diff whines at a certain speed.

My 3.23's in the 'Cuda whined at 50mph (very frustrating) but then went away as the speed increased. I was advised that this was due to (correct) pinion depth setting..............

[MilesnMiles]

Its certainly difficult to analyse from without.
My 3.23 open was silent.
My 3.91 whined due to pinion bearing breaking up
My new 3.55 sounds like the 3.91s did, but all bearing are new

[Dave-R]

Dave, i agree about the human error bit. I simply dont have the kit and experience for the black art of rebuilding.

No such thing as a black art. ;-) It is actually covered in a very detailed step by step method in the factory workshop manual.

The only bit that throws people is working out the shims needed for behind the pinion head.
The instructions call for the pinion head bearing to be installed and then measured with a pinion depth tool. You then need to remove the bearing again (not possible with out a correct puller) to install the shims needed.
However I worked out a way of getting the pinion shim depth spot on first time. As long as the depth required that is stamped on the pinion head is correct. Which you have to assume.

With my method all you need is a digital vernier gauge and three very careful measurements. Then a few simple sums will give you the shim thickness needed. The only other tool you need is a dial gauge to measure backlash. But you need that to get correct endplay on the axle shafts as well as other jobs such as checking the cam so it is a "must have" tool.

The final check is always to paint the gears with checking paste and seeing what the contact pattern looks like.

Overall, the noise offends me, but I really need to know if damage is occurring.

I seriously doubt any damage is being done. If it is ballpark then at worst the load is not being taken quite on the ideal spot (which if you were putting 800hp into it I would worry about) and it may make slightly more noise than normal. But apart from that I am sure it will be fine.