chevy rearend gears

Ok, I have a 55 chevy belair 2 door sedan, It has the rear end it came out with and 4:10 gears. That's to low for todays highway speeds. My ? is what is the tallest gears that fit that housing? I have 3:23 in my 56 And it's ok at 70, but it has a 10 bolt in it. Thanks for the help

 

depends on what kind of housing you are using?

 

If the rear ends are both stock (pumpkin bolts in at the front) the pumpkins are the same up to, I believe, 63 or 65. You can find up to 3:23's, 3:07's, maybe higher.

 

3.55 is the highest you can go in the stock 8.2 third member and 64 is the last year for that diff they are basicly the same before that

 

Third members are the same through '64. lategreatchevy.com has 3.08, 3.55 and 3.70 gears available

 

i got my gears on E bay, that 410 will sell good on E bay

 

The 55 moredoor I had years ago came with a 6 cyl. and 3 spd. no OD . It had 3.90 gears and it worked nicely with a built 265 with 8:20 X15 bucrons (Say Atlas cheater slicks) on the rear . Samo -Samo 55--64 drop out front pumpkin some changes on pinion yokes and carriers. Mopar posi side gears will work for 30 spline axles.

 

OK, let me clarify alittle. My 55 has the stocker with 4:10's in it. It's not a 10 bolt, It's the pumkin stile. I have a 400sbc/TH400 tranny, I don't want to go to a 700r4, would rather change the gears in the rearend. Can I get 3:08 or 3:23's for this housing? I didn't know if they used that high of gearing in the tri-five chevys or not. I also have a 56 that's done with a 396/4speed and a 10 bolt with 3:23's thats talerable, would like to have 3:08's in it but the clutch and the hills wouldn't go together well.

 

the pumpkin should take the gears fine, but you may need a different carrier. or a posi unit for 3.08-3.91(?) gears

 

Cool, I will be looking for the whole pimpkin with 3:08, 3:23, or maybe even 3:55's. Thanks guy's

 

I have a set of gears,,,4:86 if ya want ta get low

 

Just a nit picking deal but 4.88 was the high 4 ratio offered back then. Kinda splitting hairs but this IS the HAMB

frank

 

Richmond shows that there were two carriers for those rear ends.

http://www.richmondgear.com/07pdfs/RG11.pdf A 3 something powerglide rear end shouldn't be that hard to find in early 60's full size cars.

 

lategreatchevy.com has spacer to install a 3.55 and down ring and pinion in a 3.70 and up housing.

http://www.lategreatchevy.com/dept.asp?PageNumber=1&dept_id=247&level=1

 

The pumpkins are interchangable from 1955 - 1964. Generally the PowerGlide and TurboGlide cars from 1957 - 1964 had 3:36 gears. Some did have 3;08's, though, (seems like this was some of the 1960 - 1964 cars). It would depend on what engine and trans. the car came with. If you put a Posi in a 55, 56, or early 57 the axel shafts will have to be shortened. Here is a link to a Chevy manual site. http://chevy.oldcarmanualproject.com/ . It has the manual listed that shows this procedure. Positraction was a mid 1957 addition to the option list, so mid-late 57 axel shafts should be OK. By the way, 57 and 58 Posi cases DO NOT have a P cast in the case. My 57 has it's original Posi pumpkin, which is stamped as a 3:36 Posi, but DOES NOT have a P cast in it. It originally had a TurboGlide trans. Fortunately, it was changed to a 4 speed before I bought it.