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...just got my car back from Breman and WOW, what performance.  the 11 month wait was really worth it.  Myproblem is that in 4th gear, it "whines"/screams like a banshee.  You can almost hear the noise over the exhaust note.  Has anyone else experienced that noise only in 4th gear? It sounds like metal on metal.

Meade

Original Post

Yes, the best Rancho pro-drag gearboxes use Weddle gears in order to match the Subaru gear ratios, and the 2nd and 4th gear whine is loud, especially when brand new.  4th being the loudest of the bunch.  They do quiet down somewhat as they wear in but the reduced helix angle, larger/coarser teeth and overall "cruder" gear all create noise but with the benefit of being able to h handle the torque of the Suby motor.

Is it full of the "LAT" oil that Rancho likes?  

When I got my box back from Rancho it came with LAT Gearbox oil (I think it might be full synthetic, not sure) and it whined quite a bit.  I know Sam at Rancho really likes that stuff, but I drained it after 100 miles or so and replaced it with 100 wt Valvoline Hypoid oil and the noise decreased by a lot.  It's a little stiff going into first while moving until things get warmed up, but after that it's fine.

I totally agree with Carey, though.....Running straighter-toothed gears will always lead to greater gear noise and, after all, the tranny is right behind the rear seat.  The gear whine from the transaxle on an IMSA racing Porsche is almost as loud as the exhaust note!

Last edited by Gordon Nichols

Floor insulation upgrade is a nice touch as well to deaden the sound, adding dyno 80-90 W gear lub for me is the best. 

I tried full synthetic, which was great when cold but not great when warm... Dyno is stiff somewhat at the start but when warm seems to do much better than RedLine full synthetic, it even made the shifting sometimes notchy. 

I also added Archoil in my tranny, and it seems to help. On Jay Leno's  

Last edited by IaM-Ray

Top down driving hides a lot of imperfections, read noise masking,  in the powertrain. 

I'll always remember in the 70's in some muscle cars the tranny made as much noise as the engine and then taking your foot off the gaz would cause the tranny to make even more noise and WHINE.

Unfortunately, type I  trannies are older technology and the best rebuilding guys sometimes get all the stars aligned and the tranny is quiet, maybe quieter than most. 

Some are quite noisy, whiny, etc. Add the changes to fortify the box and gears and your at a new level of cruder tech as Carey said. 

I think on any new build especially a coupe, a rigorous amount of sound insulation, think double should be done.  Otherwise, you will be in a drum of reverberation. 

Just saying. 

Okay, in my conversation with Carey yesterday he explained the noise and it all makes sense.  I can live with the noise;  I told my wife that I have a Becker (Beck?)  German radio I could hang under the dash but my wife said not to clutter it up and just live with my iPhone and ear buds...I think I'll just listen to my Suby Music...  And I really like the new tranny; they must have changed the gear ratios also, so that will take some time to learn new shift habits.  I LOVE IT!!

meade

Meade posted:

Okay, in my conversation with Carey yesterday he explained the noise and it all makes sense.  I can live with the noise;  I told my wife that I have a Becker (Beck?)  German radio I could hang under the dash but my wife said not to clutter it up and just live with my iPhone and ear buds...I think I'll just listen to my Suby Music...  And I really like the new tranny; they must have changed the gear ratios also, so that will take some time to learn new shift habits.  I LOVE IT!!

meade

Drive the whine out of it Meade. Congratulations on the new motor. You should get many many SPG (Smiles Per Gallon) out of it.

If yours is geared the same as my trans. you will love it. 2nd and 3rd gears really pull hard under heavy throttle. 4th gear with my tire sizes turns about 3100 at 72mph. Our engines live to rev anyway. I love taking mine up to 5500 rpms regularly. The Subaru powered cars Carey puts to together are really nice. Special Edition has this deal down in opinion and experience. Do you know what gears your trans in built with? My earlier post shows the tag that came on my rancho trans showing the gears used.

I can't wait to see what my Suby puts on the ground. Supposedly it puts out 230 hp and N/A. If it's not enough, I would contemplate installation of a small turbo. Outfront Motorsports installs several turbo systems. This installation on my Spyder would be pretty clean. The exhaust would be plumbed from below, up on top of the transaxle to the turban  and down again and out. Intake would be a direct route to the TBI port via  a nice polished aluminum air to air after cooler. I would loose the spare tire though.........Bruce

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