What RPM should I be shifting at?

[MutantNinjaTJ]

There is no shift light on my 05, I've run manual trannys on trucks and motorcycles for a long long time and you just know when to shift.

 

[Nimbley]

I sure am glad I learned to drive before the shift light was invented. I was taught that if you listen to engine and feel the power being made, you’ll know when to shift. My first manual vehicle didn’t even have a tachometer. It doesn’t matter what your gear ratio is, or engine size, or tire size. Given enough miles behind the clutch you won’t even think about it. Shifting up and down is instinctive

 

[pc1p]

I sure am glad I learned to drive before the shift light was invented. I was taught that if you listen to engine and feel the power being made, you’ll know when to shift. My first manual vehicle didn’t even have a tachometer. It doesn’t matter what your gear ratio is, or engine size, or tire size. Given enough miles behind the clutch you won’t even think about it. Shifting up and down is instinctive

If I remember correctly from my air/emissions regulatory class, I believe the implementation of a shift light was never to "teach" people when to shift, but rather what provides the lowest (theoretical) emissions and highest fuel economy. It was part of the compliance strategy for the 1990 (maybe the 1994 - I can't recall) CAA standards.

 

[Jerry Bransford]

As others have said, it's a good "training wheel" for some

I'll disagree, it does not teach the correct way to shift gears so it's not a good training wheel. Shifting at the extremely low rpms it suggests will only get those new to manual transmissions off on the wrong foot by being told to shift at inappropriately low rpms.

 

[Zorba]

I sure am glad I learned to drive before the shift light was invented. I was taught that if you listen to engine and feel the power being made, you’ll know when to shift. My first manual vehicle didn’t even have a tachometer. It doesn’t matter what your gear ratio is, or engine size, or tire size. Given enough miles behind the clutch you won’t even think about it. Shifting up and down is instinctive

Exactly. I seldom to never shift to the tach - I shift by feel/hearing.

 

[pc1p]

I'll disagree, it does not teach the correct way to shift gears so it's not a good training wheel. Shifting at the extremely low rpms it suggests will only get those new to manual transmissions off on the wrong foot by being told to shift at inappropriately low rpms.

You gotta quote the full sentence

"As others have said, it's a good "training wheel" for some and has a similar effect of the "economy leaf" screen on newer Ford hybrids"

I was referring to fuel economy, not necessarily performance, since per the owner's manual and FSM that is the purpose of the upshift lamp.

Per my 95 FSM: "The lamp lights to indicate when the driver should shift to the next highest gear for the best fuel economy".

There's a reason I pulled the bulb on mine almost immediately

 

[Nomader]

You can piss all over that light.

Shifting is a sense of feel motivated by speed, power, terrain/incline/decline, ears, etc.

It's only something one acquires through many hours of doing the 3 pedal 2 step dance.

I've been driving manuals my whole life everything from Volkswagen bugs to semis so I have a good feel for when to shift and I know what my Jeep is telling me. It likes to cruise at 60 mile an hour at 2000 RPMs on flat ground.

 

[Nomader]

this is something I struggled with, I come from messing with LS v8 cars and Subaru's ej platform, and both of those cars do great at low rpms. The jeep which I have same set up you do loves 2500-3500 shifts especially where I live in the hills of east Tennessee also still get decent mpg for what it is last tank avg 16

I'm in the hills of Northwest Georgia so yes I drive the mountain ranges too and in the mountains I do go to higher RPM but on the flat ground in the valley my Jeep likes it around 2000

 

[Nomader]

I sure am glad I learned to drive before the shift light was invented. I was taught that if you listen to engine and feel the power being made, you’ll know when to shift. My first manual vehicle didn’t even have a tachometer. It doesn’t matter what your gear ratio is, or engine size, or tire size. Given enough miles behind the clutch you won’t even think about it. Shifting up and down is instinctive

I agree the first manual I drove was a 1964 Karmann Ghia. I was probably driving manuals before a lot of people on this site was even born.

 

[RINC]

I was probably driving manuals before a lot of people on this site was even born.

 

[Nomader]

View attachment 254918

That's me.

 

[ohiopatriot]

If I remember correctly from my air/emissions regulatory class, I believe the implementation of a shift light was never to "teach" people when to shift, but rather what provides the lowest (theoretical) emissions and highest fuel economy. It was part of the compliance strategy for the 1990 (maybe the 1994 - I can't recall) CAA standards.

This^^^^

Then throw in bigger tires and other mods the OE algorithm goes out the window.

It never was the "correct" shift point, just the most "efficient" one.

 

[jjvw]

This^^^^

Then throw in bigger tires and other mods the OE algorithm goes out the window.

It never was the "correct" shift point, just the most "efficient" one.

Which begs the question, which OE configuration was correct?

42rle / 29.5" /3.73 = 2052rpm @ 70mph

NV3550/29.5"/3.73 = 2320rpm @ 70mph (nearly 300rpm higher than the 42rle)

AX-15 / 29.5" /3.73 = 2349rpm @ 70mph (nearly 300rpm higher than the 42rle)

NSG370/29.5"/3.73 = 2498rpm @ 70mph (over 400rpm higher than the 42rle)

32rh / 29.5" / 3.73 = 2974rpm @ 70mph (nearly 900rpms higher than the 42rle)

 

[ohiopatriot]

Which begs the question, which OE configuration was correct?

42rle / 29.5" /3.73 = 2052rpm @ 70mph

NV3550/29.5"/3.73 = 2320rpm @ 70mph (nearly 300rpm higher than the 42rle)

AX-15 / 29.5" /3.73 = 2349rpm @ 70mph (nearly 300rpm higher than the 42rle)

NSG370/29.5"/3.73 = 2498rpm @ 70mph (over 400rpm higher than the 42rle)

32rh / 29.5" / 3.73 = 2974rpm @ 70mph (nearly 900rpms higher than the 42rle)

The cruise RPM has nothing to do with the shift points and or the light.

 

[ohiopatriot]

No. But do you think the light was ever relevant when Jeep couldn't even make up it's mind on what the gearing should be?

Not sure where the misunderstanding is......

I suppose you interpreted my post as support for the shift light somehow.

Notice the "" around the word "correct".

Prefaced with ; never was the......"correct"

this implies that I don't agree with the use of the term.

And trying to compare gear ratios in 3 speed autos to 4 speed autos to 5 speed manual to 6 speed manuals that's a whole different discussion factoring in overdrives and engines.

So.... to directly, and without confusion answer the question whether I think the light was ever relevant......No.

 

[jjvw]

Not sure where the misunderstanding is......

I suppose you interpreted my post as support for the shift light somehow.

Notice the "" around the word "correct".

Prefaced with ; never was the......"correct"

this implies that I don't agree with the use of the term.

And trying to compare gear ratios in 3 speed autos to 4 speed autos to 5 speed manual to 6 speed manuals that's a whole different discussion factoring in overdrives and engines.

So.... to directly, and without confusion answer the question whether I think the light was ever relevant......No.

Another thing that is made clear by the various factory final drives is that when someone says "mine cruises just fine at Xmph and Yrpm" there is another guy with a different transmission and a potentially wildly different rpm for that same speed who is going to say the same thing.

 

[ohiopatriot]

Another thing that is made clear by the various factory final drives is that when someone says "mine cruises just fine at Xmph and Yrpm" there is another guy with a different transmission and a potentially wildly different rpm for that same speed who is going to say the same thing.

And that has to do with shift lights and shift points and my comment, how?

 

[jjvw]

And that has to do with shift lights and shift points and my comment, how?

You specifically? I don't care. All I know is that different trans and different gear ratios and different tire sizes all add up to different shift points.

Also, many shift too early and most are undergeared.

 

[ohiopatriot]

You specifically? I don't care. All I know is that different trans and different gear ratios and different tire sizes all add up to different shift points.

Also, many shift too early and most are undergeared.

thank you Capt. Obvious.

But you're repeatly quoting me so I figured you were responding to me specifically.......even if off topic.

Have one for me.......

 

[jeepguy03]

Ideally before redline.