cad14man

Hello,

I have an '04 2500 LARAMIE QC 4x4 CTD HO w/ 6 speed, I really like it so far for only having it one week ;D. I was wondering if someone with a HO 48re can could reply with their shift points for all 4 gears and RPM ranges. I'm new to a stick and trying to figure out RPM range is best to shift and maybe skip a gear or two with this 6 speed.

So an example would be 1st gear on 48re shifts into 2nd gear at 10 mph? and 1400~1500 rpm? etc.

I basically want to try to shift my 6 speed like an automatic, to provide the smoothest ride possible.

Thanks in advance.

kayjh

[quote author=cad14man link=board=20;threadid=21192;start=0#msg198874 date=1066665625]
Hello,

I have an '04 2500 LARAMIE QC 4x4 CTD HO w/ 6 speed, I really like it so far for only having it one week ;D. I was wondering if someone with a HO 48re can could reply with their shift points for all 4 gears and RPM ranges. I'm new to a stick and trying to figure out RPM range is best to shift and maybe skip a gear or two with this 6 speed.

So an example would be 1st gear on 48re shifts into 2nd gear at 10 mph? and 1400~1500 rpm? etc.

I basically want to try to shift my 6 speed like an automatic, to provide the smoothest ride possible.

Thanks in advance.
[/quote]

Cad,

Your question is a bit difficult to answer. With the 48re (as with all automatics) the shift points are dependent on the rate of acceleration. If I press the accelerator pedal 1/2 way down, I will get different shift points than if I depress it 1/4 of the way or all the way to the floor. If you are looking for the shift points at a leisurely daily driving pace, I can go for a spin later today and report back.

RamDan03

For what it's worth, here are the gear ratios for the 6spd vs. the 48RE automatic.

----------------------------------------------------------
NV5600 6spd.
1st: 5.63
2nd: 3.38
3rd: 2.04
4th: 1.39
5th: 1.00
6th: 0.73
Reverse: 5.63
Overall Top Gear Ratio: 2.72 with 3.73 axle and 2.99 with 4.10 axle
----------------------------------------------------------
48RE Automatic

1st: 2.45
2nd: 1.45
3rd: 1.00
4th: 0.69
Overall Top Gear Ratio: 2.57 with 3.73 axle ratio and 2.82 with 4.10 axle ratio

----------------------------------------------------------

Usually I shift my 6spd between 1500-2000 RPM during normal driving conditions. If I am hauling/racing someone off a light, I will shift it up near the rev limiter at about 3000RPM. Also, If I am unloaded I will start off in 2nd gear. I only use 1st gear for heavy loads/crawling in traffic. Hope this helps a bit

cad14man

BTW i do have the 3.73 in my truck. I find that it is easier to start out in 2nd gear, and depending on the amount traffic shift from 2nd to 4th to 6th. I spend about 60% in city traffic and 40% on the highway driving to work. I dont consider myself to be a lead foot (unless I'm in a hurry or showing off)

With the 48RE i was referring to normal to heavy traffic city driving conditions pushing the throttle down 1/4 - 1/3 - 1/2....and for the heck of of it maybe a whole shot just to see what the shift points are set at WOT. again thanks in advance and thanks for the feed back so far.

bulabula

Maybe I worked too hard today, but you've got a 6 speed manual, and you want to know at what rpms a 48RE shifts at so you'll know when to shift?

Shift when it feels good - its tough to lug her without a load out back. Try 1800 and see how she likes it. If you've got a load behind you, try 2300 or so. You'll figure it out soon enough. Thats the fun part with owning a handshaker.

moterhead

The new trucks use something called a "Tone Wheel" to count axle revolutions. As I understand it, it's mounted in the differential. All it does is send a signal for each rotation. That goes to the computer and is converted to a signal to send to the speedo. AFAIK, there isn'ta learn mode. How would the computer know the speedo was off? You can go to your dealer and have the computer reset to accomdate your taller tires.


[quote author=BIGCUMMINZ link=board=20;threadid=21192;start=0#msg199001 date=1066687072]
let me throw a twist in this thread. I have 35's on my truck now. i heard these trucks/trans's have a learn mode where it detects a change in tires size? if so how do i know this happen.
[/quote]

mymaur

Bulabula is right. You just shift when it feels right. It's not rocket science. In traffic you shift at much lower rpms and if your really trying to get up to speed you may want to wind her up to 3000 RPM to get into freeway traffic.

wannadiesel

One thing to watch out for - it's real easy to shift these trucks earlier than is best for them. They pull very strongly at low RPM but it's more strain on the engine than if you shifted later. Err on the side of winding it up if you want long engine life, lugging will hurt it before revving it will. 1500 is too low, IMO, I like the idea of 1800 to 2000 better - for normal unloaded driving. Put a load on it and you need to let it breathe, don't be afraid to wind 'er up, you can't over rev it, it's governed. And like RamDan said, 1st is for heavy work, not normally needed empty.

kayjh

My 2004 - 2500 QC 4x4 3.73 HO/48re seems to shift as follows: Moderate acceleration 1/4 - 1/3 throttle:1900 - 2100 RPM (1, 2, 3) and 1/2 - 2/3 throttle: 2,600 - 2,800 RPM (1, 2, 3).

The transmission seems to get the engine to a particular point on the tach in 1st gear, then shifts to hold it at that point (difficult to do with a manual transmission, of course).

In day to day driving (city), keeping up with, or a bit ahead of traffic, typical shift points are about 1,900 - 2,200 RPM.

Others may find shift points above this, but I tend to drive moderately. If I feel like going fast, I hop into my car.

cad14man

Thanks for the feedback everyone. So far I'm finding that shifting from 2nd to 4th to 6th appears to be the way to go.