Gearing questions

[jester]

OK, I would like to know if I can change the 3.73 gears in the 64. The rear that is currently in the car has a lite whine to it. I would like to rebuild it with 4.56 gears . Will that gear fit in the carrier ?

 

[yellow wagon]

not without a ring gear spacer. Mr Gasket makes one yet. Or try and find a 4-series carrier though they aren't easy to find

 

[walkerheaders]

some opinions:............just opinions

(1) 3.70 was the best all around ratio i ever tried with a 409-4spd you may find that yours is not actually 3.73

(2) never use a ring spacer (crown gear spacer for our northern friends ) with a 4sp destined for a hell ride. use a thick gearset designed for use on a 3 series carrier

(3) Cecil just got the very unit you are seeking to try. it sounds like he may have regretted the purchase. do you and him a favor and get it from him.

(4) last fall i sold an empty 4 series carrier on evilbay. seemed like nobody wanted it, went for $110

 

[models916]

spaced out......

You can weld the spacer to the flange of the posi if you are going to really beat on it. 6-one inch long welds evenly spaced around the outside should do it. They do make thicker gears for the 3 series case to use 4 series gears.

 

[jester]

OK, I would like to know if I can change the 3.73 gears in the 64. The rear that is currently in the car has a lite whine to it. I would like to rebuild it with 4.56 gears . Will that gear fit in the carrier ?

Would the same apply if I want with a 4.11 gear?

 

[walkerheaders]

yep......and also good luck welding aluminum to cast iron.

 

[TomO]

Learn from my recent experience......WHATEVER you do replace the crush sleeve and make sure it is of the correct design.

I ordered 4.11 thick from Stange couple months back. At that time they had one set left.

TomO

 

[models916]

4:11 is easy

Richmond sell thick 4:11. Mr Gasket sells steel spacer.

 

[chevymusclecars]

Just my two cents worth but I agree with Bob. There is no sense in using a spacer if a thick gear set is available for the gear ratio you want, You don't say much about the history of your 3.70 but if someone set the backlash too tight and the gear is too deep in the ring gear they will whine. It may be as simple as setting the backlash to get rid of the noise.

Bill