rear end question

[57chevyman]

Hey guys, I have a question. what rear end gearing do you recommend for maximum fun around town AND highway cruising?

right now with my small block 350, three speed on the floor, and a rear with 4.11 gears I have a lot of tire burning power around town, but I cant take it on the highway

[Katrina/10]

I bought the 3.38 gear set for the original axle in my 55, very happy with it.

[mr48chev]

3.38 is probably about as far as you want to go if you want to drive away from a stop comfortably but still have decent road manners. I don't remember if I ever checked the ratio in the Nova rear axle under my 48 but think it is probably 3.08 and it's a bit hard on clutches as you have to slip the clutch a bit to get away from the stop light. It did pull 20 mpg on the road with the 250 under the hood when the engine was in good shape though.

[waybad]

I have 3.08 with a 6cyl, 31x10.5x15, 5sp with .9 overdrive,, I cruise 2200 @65
it doesn't like hills but it's a lot quieter inside with the low rpm...

[_Ogre]

truk has a 3.27 gear under it with the 700r4 i get 20mpg
the 350 ramjet has plenty of tire scorching hp too
i've thought about trying a 3.08 gear set but truk runs great as is

[whitedog76]

Why can't you take a truck with 4.11 on the highway?

I used to drive a 3.90 geared van. It would tow like the blazes. Wasn't really that loud.

The 3.38 or 3.55 would be a good alternative to drop a few RPM and maintain some mileage.

[OrrieG]

Use this calculator and input the info from your drive train. Watch the engine RPM and decide now tight you want to wind it. When mine was a 2wd with a 1 ton it had a 4:56 rearend for off road use. Sucked on the highway, but usually when you get off the freeways around here speed is not a factor.

http://www.powerblocktv.com/resources/

[Speedbumpauto]

If the rear you have is in good shape, you might consider a trans change. By the time you buy the R&P and all the bearings since you're there and pay someone to set it all up, you might find a T-5 out there that has an OD 5th gear. That would be sweet, especially since you already have the clutch set up in your truck. You could also go the 700R4 route with the OD gear and have a nice cruiser with plenty of getty-up.

[57chevyman]

Originally Posted by Speedbumpauto

If the rear you have is in good shape, you might consider a trans change. By the time you buy the R&P and all the bearings since you're there and pay someone to set it all up, you might find a T-5 out there that has an OD 5th gear. That would be sweet, especially since you already have the clutch set up in your truck. You could also go the 700R4 route with the OD gear and have a nice cruiser with plenty of getty-up.

Yeah man I want it to get up and go , and keep going. I don't have much knowledge of trannys and rear ends ( the kind on trucks lol). My original thought was that my problem is I only have 3 speeds , but people tell me that the issue is the rear end gears not the tranny . I'm slightly worried that my engine doesn't have the balls that I think it has and the gear ratio of the rear end is tricking me (that was another friends opinion lol)

[57chevyman]

Originally Posted by OrrieG

Use this calculator and input the info from your drive train. Watch the engine RPM and decide now tight you want to wind it. When mine was a 2wd with a 1 ton it had a 4:56 rearend for off road use. Sucked on the highway, but usually when you get off the freeways around here speed is not a factor.

http://www.powerblocktv.com/resources/

cool calculator. looks accurate to me..around 3000rpm at highway speed.

[57chevyman]

I'm not 100% sure the gears are 411. The guy who sold the truck to me said that's what it is. To drive 60mph the RPMs are way too high.

[Rigmover]

Hi I have 58 GMC with 4:11's with 350 & TH400 at 60mph shes revving about 3000 rpm.
Stock 3:90's I had before was at 2800 at 60 rpm not much difference but I wanted a posi with detroit locker so I had to change rear ends its good around town but on hwy at 55 mph you'll get your best mileage . If you go with a decent tall tire like 29 to 30 inchers it will bring the rpm down a little more at 60mph..

Rick

[57chevyman]

I have 31 inch tires. Yea 3000 is too high to cruise at. dont want to blow up my 30 year old engine

[Rigmover]

You wont blow it up keep under 60 on the hwy LOL!!
My motor is 40 years old out of a 74 half ton that I rebuilt back in 81 and is still going strong. Its been across the country 4 times since than with no ill effects and would do it again in a heart beat.

If you want to cruise at 70 to 75 yah change out the gears no doubt 3:55 is good and still will peel tires LOL!

Rick

[ruby57]

I enjoy the rpm's from my 327 with a TH400 and 3.73 rear end gear. It feels just right at 55-60mph.

Originally Posted by 57chevyman

Hey guys, I have a question. what rear end gearing do you recommend for maximum fun around town AND highway cruising?

right now with my small block 350, three speed on the floor, and a rear with 4.11 gears I have a lot of tire burning power around town, but I cant take it on the highway

[57chevyman]

snapped a few pics of my rear,,,,

[Katrina/10]

That's not a 1957 axle.

[57chevyman]

the previous owner told me the rear is from a 1972 truck