The Stovebolt Site Forums The Shop Area Driveline "granny" low

My '46 Chev p/up has factory 4-speed transmission. I drive it as a 3-speed. My question is about terminology. Some refer to low as "granny" low. Others call it "stump puller" low. Am curious as to what is the generally used term. Thank you in advance for any & all input

sandra

Sandra,

First Gear is the term used by GM.

The other names are cute and informative. Granny Gear is a common description/name. Although, at the same ages, my Grannies moved faster than my Gramps.

Unless you are from New Jersey and then its called Foyst!

Some people call it "sub low" because, unless they have a heavy load, they treat second gear as their low gear.

"compound" is another term used used for lo gear.

In my dad's old K30, the shift knob said, "L." It then went, 1,2,3, and R.

I've got a Land Cruiser with a first gear that's good to about 5 km/h. My dad referred to it as "bull low", which seems to be the norm in my area.

My neighbor used to use his 62 C-10 and a flatbed trailer to pick up hay bales by setting the hand throttle to fast idle, putting the transmission in granny gear, and using a bungee cord between the steering wheel and the seat frame. He would walk along beside the truck and toss bales onto the trailer until it got near the end of the field, then turn it around, and walk back the other way.
Jerry

Maybe it should be "walking gear" cause that is what you get from it. Dad called it compound when in a good mood. Other things when he was not so happy. I do the same. He was a very good teacher. It will pull stumps, bigger trucks and if you have traction...cars from mud. Just not very fast.

I pulled a air-cooled VW out of a almost vertical ravine using an SM420 in 1st gear (granny gear) and a strong cable.

In the great state of Wisco, we use to call it the Creeper Gear.
Some farm implements require you to drive very slowly yet with high engine revolutions per minute (RPM)
in order to have the power take-off (PTO) shaft spin at the proper RPM needed to drive the implements mechanism at the desired speed.
Such gears are usually not synchronized.

“Nothing like a farm. Nothing like being around animals, fixing things.
There’s nothing like being in the field with the corn and the winter wheat.
The greenest stuff you ever saw.”

I learned to drive in a 1974 Chevy K10: short box, full time 4wd, heavy duty springs, no radio, no carpet, etc - you get the picture. It was a work horse and it road like a log wagon.

The gear shift knob was labeled:
L . 2
|--|---,
1 . 3 . R

"L" was non-synchronized and the engine rev'd out between 5 and 8 mph when the truck was in high range. In low range, it was half that.

Dad called "L" a "granny gear" or "granny low". In "L" and 4-low, the truck would spin its wheels before it would stall. Loved that truck.

Bill

Back in the latter 80's, I used the infamous granny gear to pull a couple oak tree roots out of my front yard. Here's a couple pics taken of the end of the propeller shaft afterwards. No, I'll never do that again. Had to chop off and keep the splined section for a keepsake.

Twisty 1

Twisty 2

One of my friends who ran a small machine shop in central California had a 12" section of 4" driveshaft tubing hung from the ceiling above his lathe. It looked like an hourglass, with three complete turns twisted into it. A driver of a Peterbilt tractor stuck in a muddy field hooked to a double trailer load of freshly-combined rice wound up his 425HP Catepillar engine and dumped the clutch trying to get unstuck. The transmission output shaft made 3 turns before the shaft shortened up enough to pull a slip yoke apart! The rear wheels didn't move!
Jerry

Rare truck. GM only made that particular transmission/transfer case combination in '74 to early '75. From what I understand, they had too many problems with snapped chains in the full time t-case from drivers dumping the clutch in Low. All later full time trucks were automatic trans only, manuals got the gear drive NP205 part time.

This part of the country they refer to that as low or granny gear and compound low refers to a 4WD in low gear and the transfer case in low range.
My 76 Suburban had that setup and there were very few situations I needed it, but when you do it is great. It would crawl along at a very slow walk.

Wow. Who would have thought you could do that!

It "ate" u-joints. I remember backing it out of our driveway, the truck would twist and buck when the steering wheel was cranked over to the right turn stop (paved driveway to paved street). Looking back, I should have know better, but that's how Dad did it. One summer we had to have all 6 u-joints replaced.

We didn't use low often and eventually put a Warn part-time conversion kit into it. It almost doubled the gas mileage in town.

Premature U joint failure was a common problem on the full time trucks, even the automatics. The twisting and bucking is also a problem with those, though I don't recall either one of the 3 full time trucks we had doing it too much. But I have seen it on trucks and suvs I've had in the shop, especially Quadratrac equipped Jeeps. Even the modern 4x4s with the "automatic" 4x4 systems will do it "auto" mode, which is really just a variant of the old full time system, using a fluid clutch instead of a center differential.

There's a good reason for the twisting and bucking a 4WD with Cardan-type U joints does in a tight turn. (They're the ones with the cross-shaped center, not CV types). A Cardan joint can only flex through a very limited range of motion, and if it approaches its limit, something has to give- - - -either the angle of turn must straighten out, or something will twist or break. On loose gravel, ice, snow, or such, the tires slip and squirm, providing relief for the bind. If the tires get a good grip on dry pavement, joints break, shafts or frame rails twist, or the steering wheel bucks back against the driver's hands enough to relieve the bind. That's why front wheel drive vehicles must have constant velocity U joints that can turn through a larger range of motion without binding up. A Citroen 2CV front-drive car has Cardan-type U joints in the front axkes- - - -anybody ever driven one of them? They squirm and wobble around every turn!
Jerry

Can't say that I've ever had the opportunity to drive a 2CV, Jerry. Sound like a lot of fun in the turns.
Now that you mention it, though, something I always found odd was that when GM went to Spicer sourced front axles for the 4x4 models, they went form the Rzeppa constant velocity joints to the Cardan style. To me, that looks like a backwards step as far as performance. Only advantage I see is reduced cost. Jeep did the same thing, though the later downsize Cherokee did go back to the CV joints towards the end of their production with solid axles.

Miss Churck In the corn belt we call that gear dual low. Low axle. lowest trans gear,thus dual low.

Up here in the mitten state we call it creeper gear or granny gear, my first new truck was a 1974 GMC K1500, 350 engine, full time 4wd, sm465 trans. I was a senior in high school and got tired of wrenching on my '67 C-10 so I bought the '74 off the dealer lot.

I call that gear my parking brake.