joshua022

iTrader: (12)

I haven't found 4.30s yet, I noticed a lot of other makes can get that gear, so I added it, but I can't find them for a gm

joshua022

iTrader: (12)

390/366 on a decent tune but after the gears vengence racing will re-tune it and maybe get more out of it.

StrokerAce03

iTrader: (7)

Stay with 4.10's IMO and adjust your tire size to make up the difference. Also, going to a numerically higher number (like 4.56) would go going with a lower gear; not a higher gear.....FWIW.

bluecajun5.3

iTrader: (31)

good advice

1Bear

iTrader: (1)

With your tire height and intended usage, I would stay with 4.10's as well. I do run 4.56's, but my tire height is close to 2-1/2" taller than yours and I still turn about 2300rpm at 70mph. Which isn't too bad on gas, but mileage seems to start dropping fairly quickly at anything much past 1900 to 2000rpm. Now if your truck became primarily a track vehicle (damn the mileage), we need to know what rpm's your shifting at, to calculate the gear ratio you will need going through the lights.

joshua022

iTrader: (12)

6200 are my shift points...

I just drive it every other wekend or once or twice a week to the gym so mileage doesn't really bother me.

joshua022

iTrader: (12)

4.10s on 255/65/16
RPM 1st 2nd 3rd 4th
2000 14 26 42 60
2100 14 27 44 63
2200 15 29 46 66
2300 16 30 48 69
2400 17 31 51 72
2500 17 33 53 75
2600 18 34 55 78
2700 19 35 57 81
2800 19 36 59 84
2900 20 38 61 87
3000 21 39 63 90
3100 21 40 65 93
3200 22 42 67 96
3300 23 43 70 99
3400 23 44 72 102
3500 24 46 74 105
3600 25 47 76 108
3700 25 48 78 111
3800 26 49 80 114
3900 27 51 82 117
4000 28 52 84 120
4100 28 53 86 123
4200 29 55 89 126
4300 30 56 91 129
4400 30 57 93 133
4500 31 59 95 136
4600 32 60 97 139
4700 32 61 99 142
4800 33 62 101 145
4900 34 64 103 148
5000 34 65 105 151
5100 35 66 108 154
5200 36 68 110 157
5300 37 69 112 160
5400 37 70 114 163
5500 38 72 116 166
5600 39 73 118 169
5700 39 74 120 172
5800 40 75 122 175
5900 41 77 124 178
6000 41 78 126 181
6100 42 79 129 184
6200 43 81 131 187


4.56s on 255/65/16
RPM 1st 2nd 3rd 4th
2100 13 25 40 57
2200 14 26 42 60
2300 14 27 44 62
2400 15 28 45 65
2500 15 29 47 68
2600 16 30 49 70
2700 17 32 51 73
2800 17 33 53 76
2900 18 34 55 79
3000 19 35 57 81
3100 19 36 59 84
3200 20 37 61 87
3300 20 39 63 89
3400 21 40 64 92
3500 22 41 66 95
3600 22 42 68 97
3700 23 43 70 100
3800 24 44 72 103
3900 24 46 74 106
4000 25 47 76 108
4100 25 48 78 111
4200 26 49 80 114
4300 27 50 81 116
4400 27 51 83 119
4500 28 53 85 122
4600 28 54 87 125
4700 29 55 89 127
4800 30 56 91 130
4900 30 57 93 133
5000 31 58 95 135
5100 32 60 97 138
5200 32 61 99 141
5300 33 62 100 144
5400 33 63 102 146
5500 34 64 104 149
5600 35 66 106 152
5700 35 67 108 154
5800 36 68 110 157
5900 37 69 112 160
6000 37 70 114 162
6100 38 71 116 165
6200 38 73 118 168

4.10s on 27" slicks
RPM 1st 2nd 3rd 4th
2100 13 25 41 59
2200 14 27 43 62
2300 15 28 45 64
2400 15 29 47 67
2500 16 30 49 70
2600 17 31 51 73
2700 17 33 53 76
2800 18 34 55 78
2900 19 35 57 81
3000 19 36 59 84
3100 20 37 61 87
3200 20 39 63 90
3300 21 40 65 92
3400 22 41 67 95
3500 22 42 69 98
3600 23 44 71 101
3700 24 45 72 104
3800 24 46 74 106
3900 25 47 76 109
4000 26 48 78 112
4100 26 50 80 115
4200 27 51 82 118
4300 28 52 84 120
4400 28 53 86 123
4500 29 54 88 126
4600 29 56 90 129
4700 30 57 92 132
4800 31 58 94 134
4900 31 59 96 137
5000 32 60 98 140
5100 33 62 100 143
5200 33 63 102 146
5300 34 64 104 148
5400 35 65 106 151
5500 35 67 108 154
5600 36 68 110 157
5700 36 69 112 160
5800 37 70 114 162
5900 38 71 116 165
6000 38 73 118 168
6100 39 74 120 171
6200 40 75 121 174


4.56s on 27" slicks
RPM 1st 2nd 3rd 4th
2100 12 23 37 53
2200 13 24 39 55
2300 13 25 41 58
2400 14 26 42 60
2500 14 27 44 63
2600 15 28 46 65
2700 16 29 48 68
2800 16 30 49 70
2900 17 32 51 73
3000 17 33 53 75
3100 18 34 55 78
3200 18 35 56 81
3300 19 36 58 83
3400 20 37 60 86
3500 20 38 62 88
3600 21 39 63 91
3700 21 40 65 93
3800 22 41 67 96
3900 22 42 69 98
4000 23 43 70 101
4100 24 45 72 103
4200 24 46 74 106
4300 25 47 76 108
4400 25 48 78 111
4500 26 49 79 113
4600 26 50 81 116
4700 27 51 83 118
4800 28 52 85 121
4900 28 53 86 123
5000 29 54 88 126
5100 29 55 90 128
5200 30 57 92 131
5300 31 58 93 133
5400 31 59 95 136
5500 32 60 97 138
5600 32 61 99 141
5700 33 62 100 143
5800 33 63 102 146
5900 34 64 104 148
6000 35 65 106 151
6100 35 66 107 154
6200 36 67 109 156

joshua022

iTrader: (12)

I now see that the 27" slicks on 4.56s would probably be cutting it really close to shifting into overdrive.

joshua022

iTrader: (12)

If I can find 4.30s that is what I want. So far I can't find anyone who makes any for our trucks in that size.

1Bear

iTrader: (1)

Going off your hp numbers of 390 and guessing a weight of around 4500lbs (probably higher), I figure your capable of going through the lights around 103mph at about 5900rpm with 4.56's. So it sounds like your about right on with what your looking for. Of course if you have the actual weight we should be able to get a little closer, or if someone thinks my math sux let me know.