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I have a 52 pickup with a 235 and 3speed floor shift with open driveshaft. I don't have a tach but it sure has hi rpms on hiway speed. Any recommendations? change rear end gears or o/drive? I was thinking if I change rear gears I may not have enough acceleration around town. I just got the truck so I'm new to this. Thanks for any input-Gordon

Greetings Gordon, that is one of the most talked about subject here. If you do a search on Patrick's gears you'll learn about the 3.55 gears kit available for your truck's rearend. Another popular option is switching to a T5 transmission and an open driveline. Any increase in speed will require added braking and handling capabilities, some will say.
Hope this helps,
rick

The closed drivelines on the 52 1/2 ton had 4.11 gears for sure. However you truck now has an open drive and it still has higher than you would like rpm's corrrect? While the expense of changing the old rear over to 3:55's gears in the old closed tube axel is an option and expensive. You might want to determine what the rear you are now driving has, so you have a starting point. One of the easiest methods is to pull the rear cover and count the teeth on the ring gear and the pinion. Divide out and this will give you the exact ratio. A good all around gear is 3:08. Try and get a newer rear aprox the same width as the current open driveline. Late model chevy trucks are nice and many of the two wheel drive rears are 3:08. Look around at the pick-and-pulls. While you are out there looking try and get some S-10 rear lower shock mounts. Good luck.

I have a set of 2.73 posi. under my 57 (at least that is what I believe 41/15 is) that looks to be from a mid/late 60's GM car that I hope will give me low rpm's on the highway. Does anyone recognize this set up from anything in particular?
I know that this means my truck will never haul anything larger than say an encyclopedia set, but it was free and a five lug to boot. I have a rear end out of an 89 Firebird but that is to go into my 66 Lemans Conv. along with the 700R4 and 5.7. So when I win the lottery and can quit work to play with these full time you can bet I will have fun.

Why get your hands greasy?
Try this:

"Jack up one tire if you have an open diff, or both tires if you have a working posi or locking differential. Rotate the tire one full revolution for posis and lockers and 2 full revolutions for open diffs. Carefully count the number of full
revolutions the driveshaft makes. This is your gear ratio. In other words, if the drive shaft turns 3 & 3/4 turns, you probably have a 3.73 gear ratio. Turning the tire for twice the
number of full revolutions and dividing the drive shaft revolutions by two will give you a more accurate reading." (quoted from West Coast Differentials)

Getting greasy is half the fun.
But with any rear end that is "new to you", you would want to pull it apart, including the axles, to check the bearings and shafts for excessive wear. Better to do this in a salvage yard before you take it home than to have your "better half" get upset over the "Valdeze spill" on the driveway. Just be sure to catch the oil before it hits the ground as most of the newer yards get upset as well and may ask you not to return.

Plum,
Yes, 2:73's are a common rear gear many GM cars and wagons carried them. I have this rear in my 52 1.5 ton.
T