70 8 3/4 rear end

[metcoll]

i have the 4.56 gear in my car now and want to go to a 4.10, can anyone give a part number and source to purchase thx..

[ACUDANUT]

Either gears will not allow you to go more than 60 MPH on the highway. I have a 4.10 and my rpm's are at 4K at 60 mph, 5k at 70mph.  Great for the strip, but not for continuous speeds on the highway. 

[Birdflu]

i have the 4.56 gear in my car now and want to go to a 4.10, can anyone give a part number and source to purchase thx..

I can help you with your decision on ratio and sell you the parts...PM sent! 

[metcoll]

I had 4.10 gear in the years ago but sold them..I was happy with them..besides didnt a lot of the six pack super bees  come the 4.10..my motor is built and would work good that gear I believe

[BLK 68 R/T]

All of the 69.5 6pack/6 bbl roadrunner and superbees came with Dana 60 4.10 gears regardless of transmission.

[ACUDANUT]

All of the 69.5 6pack/6 bbl roadrunner and superbees came with Dana 60 4.10 gears regardless of transmission.

That gear combo worked well, when the speed limit was 55 MPH.  At 75 MPH Today, it would be a high revving, shot lived engine.   

[Kern Dog]

It was 1974 when the national limit of 55 mph was put into place.
I had 4.10s in the Charger for several years. It was a snappy performer but yeah...freeway cruising was a high revver.  Keep in mind, though that we have grown accustomed to lower rpm cruising over time. For MANY years, there were NO overdrive transmissions. Some GM cars had TWO speed automatics!

[b5blue]

  Most of these cars are used so little it will not matter, 4-10's are good for trailer ramps and trips to Burger Shack on Saturday.  3-23's best all round street gear for a driver.

[johnnycharger]

I have 4.10s and wish I had something better.....

[c00nhunterjoe]

"Better" is in the eyes of the user. If its a weekend warrior cruising backroads or light to light, sure put some gear in it. If you want a low rpm cruiser at 85 mph, better stick with some 2.76s.

If you currently have 56s and are looking for 10s, i ask why? The rpm change from the two is negligible for the most part. Roughly 500 rpm difference between the 2 gearsets. If it is from a performance need at the track, that is understandable. If the desire is to drop the rpm at cruise, i might suggest a 3.91. Not a huge jump from 4.10 to 3.91, but from 56s to 91s it will be more noticeable on the tach at highway speeds. Again, comes down to what you are trying to accomplish.

  To the part numbers- depends on what 8.75 pumpkin you have.