do 3.90 gears whine??
- Thread starter auyon
- Start date
thats aftermarket gears for you, my 96 cobra had ford racing 4.30s in it, in they still made some noise.
Motive 3.90 gears here, had them in for about a year, and they still whine...get a louder exhaust. CobraBob's shifter gaskets and new shift boot seemed to help the whine a bit. When i went to change my shifter the stock boot was riped and i could see the ground!
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I disagree. I have installed numorous gear sets and the only ones I have had whine issues with are the 3.90's, (2) sets. I spend a lot of extra time gauging and shimming to ensure they are set up as close as possible.
what do you recommend. tighter? looser?
tighter. its excessive backlash that makes them whine.
also, the number on the pinion is a starting point. you still have to check the pattern on both the drive and the coast side!!
also, the number on the pinion is a starting point. you still have to check the pattern on both the drive and the coast side!!
I would like to know what your setting are for - backlash, rotational pinion bearing preload, and wear pattern? Also, what lube and differential are you running?
I have always followed this, along with a cheat sheet I was given from the Ford axle plant:
8.8 Axle Gear Install
I hate the whine and I would be interested to see what your specs are. Please let me know.
Thank you,
Chris
yes, none of us would have whine if we had SLA's.
im not sure what you're asking me.
do it until you get the pattern right and if it whines its becuase you didn't get the pattern as right as you think you did. as to which way to tighten it up to make the whine go away, well, that all depends on if its on the drive side and the coast side
setting up a ring&pinion is trial&error. the numbers are justa starting point.
do it until you get the pattern right and if it whines its becuase you didn't get the pattern as right as you think you did. as to which way to tighten it up to make the whine go away, well, that all depends on if its on the drive side and the coast side
setting up a ring&pinion is trial&error. the numbers are justa starting point.
Shelbyguy,
I would just like to understand how you set up your gear sets that is different from how I have always performed the install. Which wear pattern do you shoot for?
If you reduce the backlash (or tighten the gears) you impact the wear pattern. I agree that the wear pattern is the key but in my experience the (2) go hand in hand. I have always worked toward an 0.011" - 0.012" backlash target along w/ the proper wear pattern. I have tried both ways - working strickly off the pattern and starting with the backlash. In the end, boths way have taken me to the same outcome - shim wise.
Thank you,
Chris
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Ken,
Thank you, but I would like to request specific installation/set up details. It seems like there are atleast a hundred of us that have minor whine issues and now three that don't. Please help me determine what the specific issue is. :beer:
Chris
Chris, sorry I am not more help on this one! I was more or less replying to the OP. I too though am interested in the How-to part in getting them not to whine, because I will build my next rearend for my next car myself. This one I had built in early 2004 by John Gotera of Gotera Racing / Gotera Automotive. So I don't know the specifics of what he did! His number for Gotera Automotive is 901-382-5050 (or at least was in 2004) if you want to give him a call and see if you can pick his brain a little. When I talked to him then, he had said he was doing alot of the 3.90 gear set-ups and they seemed to be the most popular verses the other offerings I was considering (3.55s 3.73s, 4.10s) so he must have them down pretty good.
Ken:beer:
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