I just switched gears in my 12 bolt with a used set from another 12 bolt, same ratio, 4.10 Richmond. I recently broke mine and a friend of mine had these that he removed to go with a 3.42. I fought with these things all day and just couldn't get a pattern I was happy with. My old gears had a .032" pinion shim and always had just a little gear whine between 30 and 40mph, then it went away. I tried the .032" shim with the new gears but the pattern was way off toward the heel end on the drive side and way down toward the toe end on the coast side. I tried pinion shims from .028" to .038 and backlash settings all the way from .005" to .012". I ended up with what I felt was the best I could achieve with a .038" shim and .0085" backlash. With that setting felt the pattern was a little too deep but otherwise had the best pattern so far. BTW, .008 BL was etched in the ring gear. I finally put it together and now I have a whine from about 30mph through 50mph. I only put about 5-6 miles on them so far but I want to correct that whine so I didn't want to drive it too far. Any suggestions?
OK first off Did the gears whine in the other guys car? OR do you NOT know that info. You just may have a set of gears that will never be quiet. .035 probably will be right on... You said it looked to deep. You may get that heel pattern because if he was ALWAYS pounding on the rear light to light you may NEVER find the correct pattern from just a spin and compound. LOOK to the coast side for your pattern on used gears. CROSS them fingers and go for it. ALSO go by FEEL. If it feels smooth both ways across the gears face you are probably close as your going to get.
He said they were quiet but his car is so loud that I don't how he could have heard them even if they were noisy. As for always pounding on it, I seriously doubt if that car has ever been out of the garage without doing at least one wild burnout. I'll get some pictures in an hour or two when I get the cover back off.
Here's is where it is right now. As I stated earlier, it's too deep but it is a close to being in the middle of the tooth as I could get it. This is with a .038" pinion shim and .085" backlash. I'm going to try a .035" and see where it gets me.
Yep too deep. Take out about .003 and try again widen the back lash to .010 t see what you get. jIM ps i THINK YOU MEAN .0085 ON THE BACKLASH correct? Jim
Here it is with a .035" pinion and .005" backlash. Now I'm going to go back and try an .008"-.010" back lash. Be right back
Keep it there at .0356 and do .009 or .010 That is the best your gonna get the drive side is just plain whooped. :0 TAke what you got and see how it goes. This is what happens when you get other aftermarket set-up gears used from someone else that set them up. It happens BUT your going to be alright even if you have a little noise. It is NOT going to blow up and I was going by the coast side ONLY Drive side will do what it can do to DRIVE you nuts on the set-up. WELCOME TO MY WORLD OF HELL... Jim :3gears: :3gears: :3gears: :3gears:
IF you want to continue to play try .033 and see what that gets you on the pattern I know you said you did it already BUT you never know you may have had dirt or grit that threw the pattern off? Never KNOW. Jim
Yeah, now I know what you mean :grin: I tried a .033" but it got worse so I went back to the .035 and ended up with a .095" BL. Here are the results. Unfortunately the whine is still there. I guess I'll just live with it for now, maybe get new gears later on. Thanks for all your help, Jim :TU:
.033 looks better to me than the .035 if that is the picture you just posted. How does it feel? When you spin the ring forward and backward. If it feels equal in both directions your probably in there. Jim
No, the final picture was what I decided to use, a .035". The .033" didn't look god so I didn't even snap a picture of it. It seemed to feel fine when I spun it so I went with it. I'm real tired of being under the car and my arms and shoulders are sore from lifting that unit in and out so I might have just given up for now. At least I can drive it to the cruise night tonight. I guess I'll just plan on new gears in the future but right now I'm outta time, I have to remodel a bedroom that we've been putting off. My sister-in-law and her kids are coming to visit next month. We got a new bedroom set already and it's all stacked in our family room right now. Don't you just hate it when this stuff interferes with our cars? :laugh:
OK well it did not look too bad... I am wishing you the best on the quietness ...crossing my fingers. JIm
wonder since its not that bad if you could add some lucas additive to quiet it down a bit? no real world experience here, just curiosity
I drove it about 60 miles round trip last night to a cruise night. Since it was hot outside we had the a/c on for the trip there. The whine starts around 30mph but it's faint, gets to where it's noticable around 40mph, is loudest at 50mph, and goes away around 55mph. It had cooled down by the time we left for home so we put all the windows down and wind blowing through the car the noise was barely even noticeable, even at 50mph unless you were listening specifically for it. I was, of course, but I doubt if anyone else would have paid any attention to it. Maybe all I need is better floor insulation in the car :grin:
Like I said it may never go away BUT it will not blow. As long as you torque all the bolt correct and the backlash is where you said it was with the correct bearing preload on the carrier bearings you will be find....IF you can handle the little bit of whine. Jim
