The Stovebolt Site Forums The Shop Area General Truck Talk 56 MPHin my 3/4 ton

I finally got my truck out on the highway. I did a short stretch about 2 miles between exits. I think I could have done a little better if I gave it a little more time with my foot on the floor.

The road was pretty flat and I got 56 MPH out of the 3/4 ton with 4:57 gears. I have larger than stock tires so I used my GPS to track the speed. It tells me my speedometer is off by about 5MPH depending on the speed.

I hope to swap out the differential for a 4:10 soon and get a front end alignment. Then I think she will be "modern" road worthy.

Rich

It's those new emblems that made it go faster. that gps is amazing stuff isn't it.

Most guys are afraid to wind 'em that high.

They were driven 60 in the 50's on roads that were straight enough to drive 60. If your rods are shimmed right and you have enough oil in them, it doesn't hurt them. My father used GMCs because of the pressure oil and precision bearings, but other than that there's not that much difference. The noise scares many people these days. Steel fans with no fan clutch and solid lifters and no insulation under the hood makes noise, but that doesn't mean anything is about to fly apart.

My concern was that my mechanic (me) has had no previous experience putting an entire truck together from its basic parts. Every nut, bolt, wheel bearing, tie rod and motor mount was installed by the cheapest labor I could find (me again).

I need a front end alighnmet but I was suprised that the front end seemed to smooth out as I past 50mph and she handled better than I thought.

Monster - those emblems looked real nice with the wind blowing over them.

Crenwelge - This is a 3/4 ton with a 216 and 4:57 gears. I was suprised I could get it over 50. Your right it was a little noisy but not bad. I insulated my cab pretty well, floor, ceiling, back, firewall...I am sure it could have been worse.

I can't wait to take her out again...if it eve stops raining here. We have had rain 4 out of every 5 days for the last 2 months.

Rich

I don't think you can find lower numerical ratio gears for a 3/4 ton rear axle. I ended up adding a Gearvendors .78 overdrive to my 3/4 ton and now I can cruise at 70.

Joe, your truck is gorgeous

Joe,
I have an Eaton HO52 rearend. The differential from the Eaton HO72 should swap out. Those were made with 4:10 gears in the early 70s. There are a few bolters on here who have done it. I am on the search for an Eaton HO72 to try it myself.

I found one at eatwestautoparts.com. Just aing for them to confirm the gears before I buy it.

Rich

Yeah Joe that is a gorgeous truck

Thanks Rich and 53 Monster.

I wasn't aware that the 53 had a different rear end. Mine is a Dana in the 51.

I would hate to see many years of research and discussion on the forum distorted by misinformation so unless I’m really misinformed myself, the Eaton HO72 uses exactly the same carrier as the Eaton HO52; it is the 1-ton version of the axle housing however. The differences being in the backing plates brakes and drums. There was never a 4.10 available in the Eaton HO72 and in this version of the Eaton rear axle you are most likely to find a 5.17 gear ratio and occasionally the option of a 4.57 gear ratio. There have been many discussions on this subject over the years and by reviewing the archives you should be able to verify this.
The 4.10 gear was used in some 68-72 3/4- ton trucks with automatic transmission. Mine came out of a 1970 3/4-ton V8 automatic pickup.
Very nice looking truck Joe, but if your 51 has a Dana rear axle in it then it has been changed from what was originally installed at the factory. Your single picture does not indicate what engine, transmission, rear axle was installed in the truck but I would assume that if it has a Dana rear axle that the engine and transmission have also been upgraded.
Denny Graham
Sandwich, IL

Ahh, another 216. I'm not surprised you can do 56. I've never taken my truck over 50, its a 216, with 5.14 rear, being a one ton. It will cruise at 50 mph with 2200lbs in the box. I generally drive 45mph though.

Looks great Rich.

That's where I am trying to get mine. I have a line on a 72 3/4 ton V8... not auto though so thay are going to pull it apart and let me know the gears before sending it.

maybe I mis-spoke on the HO72 confusing it with the year which is 72

If it's not an automatic then chances are it is the same as the gear in your truck, a 4.57.
DG

Denny,,,you are correct

Could you please explain what gearvendors are and how they work?
Thank-You,
Jimmy D>

A Gearvendors is an overdrive unit that bolts on the back of the transmission to give a .78 ratio in 2nd, 3rd, and 4th gear. You end up with 7 speeds, although I've never really used it in any gear but 4th. Here is their web site.

http://www.gearvendors.com/index.html

Joe, Is that .78 really $2895 or am I lookinag at the wrong thing?
Rich

Nope, that's it. The Gear Venders unit is very spendy. The Ranger Overdrive is another option along that line. Less expensive, but still requires driveshaft alterations to work, plus a hole in the floor for the shifter.

You fellows better catch up.Had my 51 going to Datona the turkey run this past turkey day 130MPH on the GPS.No problem.backed off or could have gone a little faster.9'ford rearend,700r4tranny,350cu thats pushing375hp

No, thanks, dan-pa. I like 50 - 60 mph for a fast cruise, and I like the song of my in-line six.

There are times I will run balls-to-the-wall, but they are few, far between and limited to very lonely, twisty mountain roads when I am alone on my motorcycle.

Rich, the Gearvendors is expensive, but you don't have to change axles and can eliminate the center bearing in the drive shaft due to the 20 1/2" length of the Gearvendors unit and use a single drive shaft. Unlike the Ranger overdrive you don't have to cut a hole in the floor for the shifter since the Gearvendors is electrically operated. I used the throttle knob on the dash remounted on a push-pull switch to activate it.

In this part of the country they don't hand you a ticket if you're caught doing that kind of speed, they cuff you.

I've run three figures in a pickup. I guess I'm old now, the thought no longer interests me.

dan-pa,
do you have any pics of your truck you could share ?
sounds like you got a killer truck...

leonard

Ranger overdrive in action. It's toward the end of the vid.