4.55 gears and 3 speed

[James_Douglas]

Hi Folks,

 

James from over in the car forum.  I wanted to ask if anyone here has a 4.55 rear and is running the 3 speed stick. I would appreciate you driving impressions with this combination.

 

Thanks, James

[1949 Wraith]

3.55?

 

[James_Douglas]

My Car uses the 1940's 8-3/4 inch Dana rear-end. It was used in the limo's and the larger of the Chrysler 8's.

 

The problem is that the ring and pinion sets for these are no place to be found. I have been beating the bushes for months with no luck.

 

I do not want to tear it out and replace it if I can help it.

 

I ran across a set of 4.55 gears. I want to talk with someone who is running these gears with a three speed to get a qualitative sense of how they drive. I have a fluid coupling and a three speed with OD.

 

Yesterday I had a talk with someone in the Hudson Club. The late 1940's Hudson's that had overdrive were shipped with 4.55 rear-ends.  I may consider that as my 3.91 and 4.11 ring and pinion sets are not in great shape.

 

The Desoto Suburban is also quite heavy in road trip curb weight it is about 4500 pounds or more.  The flathead six does struggle on highways hills. Big mountains is especially tough.  

 

I drive the car every day in city traffic and I suspect such a numerically high ratio may would be a PITA on city streets. Right now with the 3.91 gears I can drive all day in town with second gear and second OD.

 

I am assuming, perhaps incorrectly, that some of the truck folks have trucks with the 4.55 gears and a three speed.

 

James

[LazyK]

using this calculator  https://spicerparts.com/calculators/engine-rpm-calculator

4.55 gear,30" tall tire, 1.1 gear ratio(3rd gear no overdrive), and a 55mph speed limit, your engine RPM would be 2548

[Merle Coggins]

I believe only the 1 ton truck differentials are compatible with your diff. The 1/2 and 3/4 ton trucks share a diff with the 'every day' cars. According to my parts manual these were available in 4.1, 4.3, 4.89, and 5.625 gear ratios. There was never a 4.55 ratio for this size truck. 

[Dodgeb4ya]

BTW...afaik  1940-52 crown Imperial 3.58 pumpkins will bolt right in a DT 1 ton.

Change the yoke....increase engine horse power...good to go.

[Merle Coggins]

This morning I saw a post on the Pilot-House FB group. There’s a gentleman trying to unload a 1 ton chassis in Reno, NV. Might have a viable differential for you… 

https://www.facebook.com/marketplace/item/374000674060289/