47-55.1 411 gears

[48gmc]

have a 48 gmc 1/2 ton, has 411 gearsin it want to change to a 3 something gears, what is involve to change over, never done it before.

[mongocanfly]

if you've never done a gear change before , it can be quite a challenge...
it can be a challenge even for a experienced mech sometimes...
it can also be expensive to have done...best option is find another axle..
the ratios depend a lot on tire size, final gear of transmission, and the desired cruising speed
what axle do you currently have?

[48gmc]

i have the torque tube

[mongocanfly]

sounds like its time to upgrade the drivetrain...

[1957 Chief]

Originally Posted by mongocanfly

sounds like its time to upgrade the drivetrain...

What he said...

I have a 49 and I was looking into the same area...gears. Then I decided to get a 58 truck rearend and add a factory 59 Bel Air Borg Warner overdrive transmission to the truck. Cost me less to do that, than to do a gear swap with all new parts. I think I have less than $500 in the swap over.

Bubba

[48gmc]

get a axle and driveshaft, then change gears, that is alittle bit of money. do you know what axles would fit

[mongocanfly]

Gear swaps for your axle wont be cheap either...if you can find any...are you sure its 4.11 gears?
Theres many threads on AD axle swaps...heres one...http://67-72chevytrucks.com/vboard/s...d.php?t=420560

[48gmc]

something to think about, thanks for the help.

[mr48chev]

There are 3.55 gear sets available for these trucks. Guys used to get them from Patrick's But There were a ton of threads about guy ordering and never getting them or being back ordered for months.

Classic parts shows the ring and pinion and bearing set but you are looking at just under 900 for parts with no labor and this is one job I farm out if I can. It is a level or two above rocket science to get it right.
https://www.classicparts.com/Rear-En...s/products/71/

Even if you find better prices on the gears and bearings you are looking at several hundred dollars labor and will have 1000 to 1500 tied up in the rear axle.

It's not our place to judge what folks spends on certain parts of their truck or why they spent it. I'd say that the majority of us work on relatively tight budgets and Will look for the most economical way to accomplish something while staying somewhat inside the lines.
The normal swap for years was to use a 55/59 open drive rear and as suggested maybe an overdrive transmission. Or find an axle with more desirable gears.
Doing some searching for another member I found that some years of Toyota Tundra 4x4 rears are the same width (within a 1/4 inch) as the stock rear and have the same bolt pattern. A guy has to snoop on the Tundra forums to find the gear ratio codes and I don't know what they might go for locally in your area. Here those trucks are everywhere and there are plenty of them in the wrecking yards.

It just depends on what yo want the truck to be as some guys who are bent on having an "original" truck would never swap to open drive no matter what as then it isn't original anymore.

[48gmc]

do you think a regular drive shaft would fit my original 4 speed

[mongocanfly]

there are conversion kits to go from torque tube to open...but they are pricey..
if it was me . id change trans and rear axle...nothing you do is gonna be a quick/easy/cheap swap.....

[Jemezcrusher]

You can put an S10 5 speed with overdrive (.76 or so) that will bolt up to your original bell housing. You have to change out the input shaft but is easy. You can use your original clutch. Go to the Upull and pay in your area and get a rear end out of a Explorer. There is a span of those that have 3.73 posi with disc brakes. The other ratio available is 3.55. Older ones have drums. I picked mine up for 125 out of a 2000 model. New bearings, brakes and gears brought the total up to about 800 but everything is new,. New driveshaft (51.5”) for 200.00 from Southwest Speed brought the total to about 1000 plus the transmission. I got it from Upull for 125 and put bearings in it and the input shaft. So for about 1300, I put in a freshened trans, new drive shaft and rear end. Final drive ratio in 5th is 2.85 would should give me a 70 mph cruise without running the motor at crazy rpm

[48gmc]

thanks guys for all the info, still snow here so i got time to think what i want to do.nothing is cheap or easy, thanks again, i will on again sometime for more info.