Do all new Richmond Ring and Pinion gears make noise ?

[Man In Black]

I'm looking to take the 3.90 gears out of my 72 and replace them with the new stock ratio 3.36's and the only company that I can find that sells the 3.36's are Richmond gears which I was told that they run a little noisy. Has anyone run into this and can advise. Is it because they are a high performance gear and it is the cut of the gear ? Thanks

 

[kpic]

Gears make noise at a frequency where us humans can hear it.

A ring and pinion are hypoid bevel gears; or a type of a spiral bevel gear where the axis (center) of the ring gear is offset from the axis (center) of the pinion.

Richmond Gear Camaro gears - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums - Camaro5.com The user's screen name is Richmond Gear and it is a very good read on the subject.

 

[GTR1999]

I don't know how you are talking to but there are 336 gears made by other companies then Richmond. Richmond, Yukon, Motive, and Toms ( US Gear) all make vette gears but only Tom's are made in the USA. The others may even rebox his and sell them. Many vendors use Tom's and rebox, some tell you whose they use, others don't. Call Tom and buy your gears direct.

As for noise. I have set up Richmonds before and never had a problem until the last set I used a few years ago. The lash and pattern were perfect and they howled like hell. I replaced them with Tom's 355's and solved the problem. Richmond used to make gears in the USA until about 3 years ago when they were bought out by Mid West Truck which also owns Motive , made outside of the USA.The only gears I use are Tom's.

With any gear installation, lash, preload, and pattern will determine how well the gears will respond. Vette ratios are avail in 308, 336, 355, 370, 373(PREFERRED OVER 370), 390(Richmond), 411, 433, 456.

 

[kpic]

I'm looking to take the 3.90 gears out of my 72 and replace them with the new stock ratio 3.36's and the only company that I can find that sells the 3.36's are Richmond gears which I was told that they run a little noisy. Has anyone run into this and can advise. Is it because they are a high performance gear and it is the cut of the gear ? Thanks

GTR1999
He asked about Richmond Gear.

In my opinion, your "Richmond used to make gears in the USA until about 3 years ago when they were bought out by Mid West Truck which also owns Motive , made outside of the USA." is probably the answer.
I'm not much for offshore manufacturing; I prefer American made for the obvious reasons.

True, all it takes is a Gleason and tooling.

Was the noise under load, coast, or both?

I haven't been involved with hypoid bevels since 1990. Typically the gears were cut, (then Heat Treat machining the mounting surface etc. can be ignored for what we are discussing), lapped and a tooth contact test. After lapping, the ring and pinion are a matched pair, never to be separated.

Getting too deep for the OP's question.

 

[kpic]

GTR1999
This is from a friend who is a manufacturing engineer; he oversees machining ring and pinion sets and other differential related machined products (rolled splines etc.) 8 hours a day.

"Interesting. Howling/moaning is usually caused by runout in the back face unless the cut is really messed up. Any report of failures? There are 4 or 5 possibilities that come to mind, espec since it’s now a Chicom product:
-They cut the quench press out of the process completely and are now free quenching the gears. Instant warpage.
-The summaries weren’t optimized for the new HT process. It’s usually an iterative process. Cut, HT, adjust cut to compensate for warpage, etc. Every HT process is unique so a US summary will need tweaking for a Chicom furnace.
-Cutter head build is incorrect and/or they’re running the blade groups too long/dull. You’d have ridges, poor surface finish, etc. that couldn’t be fixed at lap
-Using incompatible processes (Gleason cut pinion with Klingelnberg cut ring gear for example). The gear set would physically work but have all kinds of issues.
-Metallurgical issues. They might be using a summary developed on good alloy (high nickel) to cut cheap material."

I said offshore and he assumed China.

Although when you set up a rear you check the pattern's (mesh) or contact between the ring and pinion. The assembler adjusts the pattern to its correct shape and location. When a ring and pinion is under load they deflect. The contact is huge compared to what was measured during assembly.

Neither of us are violating any company information; what he listed are general causes which create "howling" which can be learned in any class on this type of gear. The answer would have been "better" if we would have known the answer to my drive or coast condition or all the time question.

 

[GTR1999]

GTR1999
This is from a friend who is a manufacturing engineer; he oversees machining ring and pinion sets and other differential related machined products (rolled splines etc.) 8 hours a day.

"Interesting. Howling/moaning is usually caused by runout in the back face unless the cut is really messed up. Any report of failures? There are 4 or 5 possibilities that come to mind, espec since it’s now a Chicom product:
-They cut the quench press out of the process completely and are now free quenching the gears. Instant warpage.
-The summaries weren’t optimized for the new HT process. It’s usually an iterative process. Cut, HT, adjust cut to compensate for warpage, etc. Every HT process is unique so a US summary will need tweaking for a Chicom furnace.
-Cutter head build is incorrect and/or they’re running the blade groups too long/dull. You’d have ridges, poor surface finish, etc. that couldn’t be fixed at lap
-Using incompatible processes (Gleason cut pinion with Klingelnberg cut ring gear for example). The gear set would physically work but have all kinds of issues.
-Metallurgical issues. They might be using a summary developed on good alloy (high nickel) to cut cheap material."

I said offshore and he assumed China.

Although when you set up a rear you check the pattern's (mesh) or contact between the ring and pinion. The assembler adjusts the pattern to its correct shape and location. When a ring and pinion is under load they deflect. The contact is huge compared to what was measured during assembly.

Neither of us are violating any company information; what he listed are general causes which create "howling" which can be learned in any class on this type of gear. The answer would have been "better" if we would have known the answer to my drive or coast condition or all the time question.

Very good information as it sounds like you are in the business.

Regarding Richmonds, from my experience, I HAD good setup with them in the past but won't use one of the new sets. That last set was dialed in perfect yet it was terrible. The Tom's gears were night & day difference. This is for the 10 bolt vette setup, that is all I do but have heard others had similar issues with other sizes. Typically the pattern with Tom's is center to toe on the Drive and center on the coast and you're correct under load it will spread.

Now with a 12 bolt vette conversion I use the special cut gears, made by Richmond- probably years ago, and they setup good.

The biggest problem I see coming, and very soon, is there will not be USA made gears for these cars anymore. This possibly could change and stay the way it is now but I don't expect that to happen.

 

[kpic]

GTR1999
Not me, he is a manufacturing engineer where they manufacture differentials. I used to design engines, transmissions, differentials and transfer cases.

Years ago, other than looking at where the "paint" peeled off during meshing, there wasn't a means to measure the deflection under load.
Nowadays a lot more can be done using computers:
http://www.mie.utoronto.ca/labs/emdl/people/stranart/mie222/fact_sheet/fem/image39.gif

The above is an idea of what can be done. I found it online by searching for FEM analysis of a bevel gear; I had nothing to do with it

More and more of America's manufacturing is going overseas taking good jobs with it and I don't see that changing either.