The sound of 3 speeds

[Fantuzzi]

Hi members,

my question is directed to those, who runs their 3 speeds. My Bruiser`s gear box is fairly loud in first and second gear compared to modern gearboxes. No problem so far. In third gear the gearbox is quite and smooth like a Stealth Bruiser.

What about your 3 Speeds?

[Shodog]

Mine is noisy to. at one point I put STP oil treatment in it. This stuff is a thick oil viscosity enhancer. It really quieted the tranny but since mine isn't sealed with silicon. The stuff leaked out over 8 months. I had to keep a pie pan under the truck just like a real car.

[J3cubfan]

LOL, you don't get much realistic than that. Although, I don't think that the Toyota Trucks leaked oil much[]

quote:Originally posted by Shodog

Mine is noisy to. at one point I put STP oil treatment in it. This stuff is a thick oil viscosity enhancer. It really quieted the tranny but since mine isn't sealed with silicon. The stuff leaked out over 8 months. I had to keep a pie pan under the truck just like a real car.

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[Fantuzzi]

quote:Originally posted by Shodog

Mine is noisy to.

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Noisy O.K.

But is there such an accoustic difference between 1st/2nd and 3rd?

[WillyChang]

quote:Originally posted by Fantuzzi

But is there such an accoustic difference between 1st/2nd and 3rd?

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Yes!! Check the gearbox blowup diagram...

• When you run in 1st, the drive goes through spurshaft, 2 layshafts and 2 output shafts. The path is like a "W".
  
• In 2nd, it goes through spurshaft, 1 layshaft and then output shaft. Path is a "V".
  
• In top, its spurshaft straight through to output shaft. The whole gearbox is avoided, path is "-".
  

Naturally there is a big difference in noise; that noise is the sound of your gears grinding themselves away... []

STP, Wynns and all the other engine-oil friction modifiers (check your local autoshop) will eventually leak out, even the thick-as-honey ones. Tried a few but Bruiser #1 still runs quietest on 3-in-1 but it needs a drip pan and worst still, it can drip whilst running (think carpet[V]).

Subsequent Mounty I pulled apart the (used) gearbox and completely flushed out all the accumulated metal filings and gunk. On reassembly I lubed everything -especially the inner bushings- with moly grease. Outer bushings replaced with BBs. This gearbox runs quiet, changes smoothly & no drips.

[Tamiya King]

The only 3 speed I have is in my King Hauler. It runs smooth as a babies bottom. But mine is brand new. only run 4 times, shifts real good too.

[DJTheo]

quote:The only 3 speed I have is in my King Hauler. It runs smooth as a babies bottom. But mine is brand new. only run 4 times, shifts real good too.

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The truck tranny is out of plastic and uses plastic gears and therefore much more quiet.

Replacing the -worn- bushings with BBs can do miracles, don't forget to use often good synthetic spray oil (for example for Motorcycle chains) or high quality grease.

Due to worn bushings or abuse, also the gears might be worn/deformed causing alot of noice/friction.