Engine RPM with the 3.73 VS 4.10

[Kirwin]

What are you guys who have a new truck seeing for RPM at 60 MPH? Is the engine noise significantly louder for the higher RPM you are seeing in the 4. 10? In my 12 valve this was the deciding factor for the 3. 55. Couldn't put up with the engine noise at 2500 RPM in 5th gear running empty. If someone would measure the diameter of your tire I can calculate the difference in engine RPM and figure it out myself. Thanks. Remember don't tell my wife, I am not allowed to have a new truck! Ken Irwin

 

[kbarlow]

Here is the 3. 73 numbers





Engine RPM v/s MPH with 3. 73 Diff. , 6 speed, tires 265/70/17







RPM 1st 2nd 3rd 4th 5th 6th Gear

500 2 4 6 9 13 17

600 3 4 7 11 15 21

700 3 5 9 13 18 24

800 4 6 10 15 20 28

900 4 7 11 16 23 31

1000 4 7 12 18 25 35

1100 5 8 14 20 28 38

1200 5 9 15 22 30 41

1300 6 10 16 24 33 45

1400 6 10 17 25 35 48

1500 7 11 19 27 38 52

1600 7 12 20 29 40 55

1700 8 13 21 31 43 59

1800 8 13 22 33 45 62

1900 9 14 23 34 48 66

2000 9 15 25 36 50 69

2100 9 16 26 38 53 73

2200 10 16 27 40 55 76

2300 10 17 28 42 58 79

2400 11 18 30 44 61 83

2500 11 19 31 45 63 86

2600 12 19 32 47 66 90

2700 12 20 33 49 68 93

2800 13 21 35 51 71 97

2900 13 22 36 53 73 100

3000 13 22 37 54 76 104

3100 14 23 38 56 78 107

3200 14 24 40 58 81 111



Excuse the formating but you get the idea.



Cheers Ken

 

[ntenna]

Ken- these new trucks are quiet enough I don't think it matters anymore. I've driven 7 or 8 of them, both ratios, and most all are MUCH quieter at 60-70 MPH.



JH

 

[Dean Upson]

Ken,



Could you do the same table for the 235/80R17E's with the 4:10 gears? Thanks.



Dean

 

[timjones]

Heres a link to check rpm vs. tire

http://www.f-body.org/gears/

if you look at make a selction (drop down at top) it has all 3 trasmitions built in.

 

[Dean Upson]

Thanks, Tim.



That is a great calculator!, now I can really impress the wifey with my wealth of nolige!



Dean

 

[Dean Upson]

I found another interesting little gem using Tim's calculator:

My 98 truck (and my 94) had 215/85R16 tires (30. 3897" dia. ), at 2000 rpm I was going 60 mph.

My 03 truck has 235/80R17 tires (31. 8031" dia. ), at 1900 rpms I am going 60 mph and at 2000, 63 mph. How 'bout that?



Dean

 

[Casey Balvert]

Don't know about your wife but I'm impressed. When I did the calculations and compared my 97 2500 with 4. 10 and the new 3500 with 4. 10 I am turning about 350 RPM slower now.