8 3/4 Whine

[rebootej]

Hi guys, I installed an 8 3/4 third member in my 74 Satellite today. It is a used 3rd member and set of gears that i bought from a local shop they went through it and patterned it.

Love the new ratio (3.23's) and its very smooth but while accelerating it has as loud whine, which goes away while coasting. Any ideas what could be causing this? Im gonna Talk to them in the morning. Does it sound like the gears were not set up right? Thanks for the help.

 

[1970GTX]

I'd find out which brand of gears they installed. I've read somewhere there have been complaints that Richmond Gear have some whining noise on new installs. Hopefully they ran the new set in before putting the car on the ground. The whine might disappear after a few miles too.

 

[RustyRatRod]

Pinion gear depth is incorrect. I used to know but have forgotten whether noise on accel is too much or too little gear depth. It's one or the other, but the pinion gear depth is what it is.

 

[MoparMitch]

If you are saying that the shop put a different set of gears in the third member than what was in it.... Then there are several things they should have checked. No. 1 the pinion depth in the case would most likely be different for another set of gears. Often the pinion depth desired will be marked on the pinion nose itself. This is the first thing to get right. After that the carrier side bearing preload and clearance between the pinion gear and the ring gear must be checked. Generally that should be between .007 and .011 in. Then they should have rechecked the bearing preload. After all that is done they should have painted the gears with marking grease and checked the pattern. I suspect that all of these step were not taken in your case. I would quizz the shop to see if they took these steps. Hope that helps.

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You guys are too fast for me. It takes me a while to peck at the keys . LOL

 

[Supershafts]

Im with RRR, that shop got the set up WRONG. . . . and after setting up the depth and BL they didn't read the pattern right and then make further adjustments as needed sometimes.

 

[MoparMitch]

I'd be willing to bet that they used the old pinion depth shims , or none at all. And.... Never checked the pinion depth.

 

[67 coronet]

some gears will whine for about a hundred miles or so as they break in.that being said,call and check with the shop for sure.ask if they have the specs you rdiff was set up with.

 

[Cranky]

Noise on acceleration means the pinion is not deep enough...and if it's loud enough to make you turn up the radio louder so you can hear it, then it's off by a good bit. Also, you shouldn't even drive it that way because you'll have excessive wear on the gears in short order. As for Richmond gears producing noise....I've been hearing this for years but so far I haven't experienced any of that. Also, if the shop used the pattern method instead of a dial indicator to set the pinion depth, you need to find another shop. That's the way I've been doing it for over 20 years and have never had any come back to me. Matter of fact, I even quit checking the pattern with the white grease after the first couple of years.

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some gears will whine for about a hundred miles or so as they break in.that being said,call and check with the shop for sure.ask if they have the specs you rdiff was set up with.

Never experienced that myself. If they whine at start up, generally, they will always whine. Had a couple that I did that had a very slight whine and 10 years later, they still whine. Also had a 90 Dakota that had a very slight gear whine and they did that for 100k miles. Took it to the dealership and they said it was acceptable but to bring it back if it got worse.

 

[Meep-Meep]

Could you give it some cheese with its whine?

I had one rear end shop say the pattern doesn't lie, implying that's it's a pretty darn good way to go.

 

[67 coronet]

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Never experienced that myself. If they whine at start up, generally, they will always whine. Had a couple that I did that had a very slight whine and 10 years later, they still whine. Also had a 90 Dakota that had a very slight gear whine and they did that for 100k miles. Took it to the dealership and they said it was acceptable but to bring it back if it got worse.[/QUOTE]

we have done many here at the shop and sometimes farm some out to another local shop that does great diff work.we had two diff situations were the rear made a slight(and i do meen slight!)whine which he said would go away.he was right in both cases.

 

[RustyRatRod]

Thanks dude. I knew it was the pinion gear depth, I just could not remember which way. Thank you drive through.

Noise on acceleration means the pinion is not deep enough...and if it's loud enough to make you turn up the radio louder so you can hear it, then it's off by a good bit. Also, you shouldn't even drive it that way because you'll have excessive wear on the gears in short order. As for Richmond gears producing noise....I've been hearing this for years but so far I haven't experienced any of that. Also, if the shop used the pattern method instead of a dial indicator to set the pinion depth, you need to find another shop. That's the way I've been doing it for over 20 years and have never had any come back to me. Matter of fact, I even quit checking the pattern with the white grease after the first couple of years.

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Never experienced that myself. If they whine at start up, generally, they will always whine. Had a couple that I did that had a very slight whine and 10 years later, they still whine. Also had a 90 Dakota that had a very slight gear whine and they did that for 100k miles. Took it to the dealership and they said it was acceptable but to bring it back if it got worse.

 

[Cranky]

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Never experienced that myself. If they whine at start up, generally, they will always whine. Had a couple that I did that had a very slight whine and 10 years later, they still whine. Also had a 90 Dakota that had a very slight gear whine and they did that for 100k miles. Took it to the dealership and they said it was acceptable but to bring it back if it got worse.

The Dakota never did go away. Very slight whine but just got used to it and it was so slight, you didn't notice it anymore. I did a Dana 60 for a buddies turbo Dakota and it hasn't gone away either. It's also very slight. I did that one 4 years ago and it's had some track time put on em. I also was told (by a shop) that a minor whine usually goes away but he also said that you usually become accustomed to it more than anything lol

we have done many here at the shop and sometimes farm some out to another local shop that does great diff work.we had two diff situations were the rear made a slight(and i do meen slight!)whine which he said would go away.he was right in both cases.[/QUOTE]

 

[rebootej]

Thank you for the advice guys! Great responses. I took it back to the shop armed with what you told me and the guy is going to redo it.

 

[RustyRatRod]

That's good. He oughtta redo it. Cause a chunk type is hard to screw up in the first place.

 

[dvw]

Once noisy, always noisy. I have found steep (4.30-4.56) Richmond gears to have slight whine during a "float" condition. That meaning neither accelerating nor coasting. A 3.23 should be quiet. The problem arises with used gears being swapped to another carrier. If the pinion depth and back lash aren't what they were in the old carrier it will generally be noisy. Reading a pattern on used gears is a crap shoot at best. ideally you should see this.
Doug

 

[RustyRatRod]

Not trying to start a war, but I disagree. If that were the case, then my Ranger would have a whine with its 4.10s. It's quiet as a mouse. My 65 Valiant had 4.30 Richmonds. quiet as a mouse. I've used Richmonds in almost everything I've ever set up and not had a whine excpt for where "I" made a mistake. Noise that can actually be blamed on "bad" gears is extremely rare I have found. It is usually the installer.

 

[Supershafts]

I have to agree with RRR, i have had people pull in with diffs making so much improper set up noise you couldn't talk, im serious i had a jeep once you past 20 mph talking resorted to yelling.

He drove it like that for 2 years, how i have no idea, adjusted it after replacing all bearings and he was in love with his bill lacking the cost of new gears.
Most times the noise is set up and the amount of adjustment to make it right can be very very little.
There are times when gears are installed and they are broken in wrong and or gouged heavily and then it is very hard to remove the whine, but you can lesson it some.

I have only had one set of some china pirated gear, that the best i could get the gear noise was to a very slight whisper and only at slack cruise did it make noise, i still wonder if i took the ring off and filed the gear like i wanted to if it would have been quiet altogether, but i didn't buy the gear and recommended to not buy it but some people are like stubborn horses, can bring them to the water....but can't make em drink it

 

[Cranky]

Once noisy, always noisy. I have found steep (4.30-4.56) Richmond gears to have slight whine during a "float" condition. That meaning neither accelerating nor coasting. A 3.23 should be quiet. The problem arises with used gears being swapped to another carrier. If the pinion depth and back lash aren't what they were in the old carrier it will generally be noisy. Reading a pattern on used gears is a crap shoot at best. ideally you should see this.
Doug

Doug, try painting the pinion gear only with the marking compound and then spin it through and see if you don't like that result better than how you're doing it now....

 

[Jasoncoronet]

From my experience certain brands do make more noise. I think like everybody is saying the setup is wrong just needs to be corrected. However i think these gears were used and the wear pattern is already established. That whine may never go away. Each manufacture has there own design what i mean is the pitch of the gear. The more straight up the more noise but also the more strength. With this said when using a strong gear like richmond setup is more crucial. If you quiet use whatever came stock. You dont want hear the whine get more horsepower louder exhaust.