new tahoe feels slow as $hit!!

[BOTTLEDZ28]

little update on this: I had a feeling that something wasnt quite right with my RPO code sticker when it told me I had the GT4 gear option. Sure enough I checked the VIN on the sticker and the VIN on the truck and they are different. Someone must have replaced the glove box at some point in the trucks life. Funny thing is the VIN in the glovebox decodes to 98 black 2 door tahoe just like I have. The only difference in the VINs is the production number at the end.

So now I have to figure out the gear ratio the old fashion way. I will do it when I do the blocks and torsion crank this weekend.

Im almost tempted to do 4.10s but I just drove 200 miles today and the gas gauge didnt move. My other 2 door would have drank a half a tank!!

FWIW, if I am doing 70mph my rpms re around 1700. I can do 80mph and still keep the rpms just under 2000. Im not sure if anyone here can guesstimate my gearing based off that but my 94 with 3.42s runs at 2,000 rpms at 70mph. Is there a possibility that I have 3.23s or even 3.08s in this ?

 

[SilveradoGuy85]

little update on this: I had a feeling that something wasnt quite right with my RPO code sticker when it told me I had the GT4 gear option. Sure enough I checked the VIN on the sticker and the VIN on the truck and they are different. Someone must have replaced the glove box at some point in the trucks life. Funny thing is the VIN in the glovebox decodes to 98 black 2 door tahoe just like I have. The only difference in the VINs is the production number at the end.

So now I have to figure out the gear ratio the old fashion way. I will do it when I do the blocks and torsion crank this weekend.

Im almost tempted to do 4.10s but I just drove 200 miles today and the gas gauge didnt move. My other 2 door would have drank a half a tank!!

FWIW, if I am doing 70mph my rpms re around 1700. I can do 80mph and still keep the rpms just under 2000. Im not sure if anyone here can guesstimate my gearing based off that but my 94 with 3.42s runs at 2,000 rpms at 70mph. Is there a possibility that I have 3.23s or even 3.08s in this ?

You probably have 3.23. I highly doubt you have a such of a high gear like 3.08, but you can't rule that out. A buddy has an 06 Sierra with a 3.23 gear and his truck gets roughly 17 mpg in town which ironically is the same as his 03 Mustang V6. But, he has the tow/haul mode to make up for it, where as my 98 Silverado has 3.73 gears which for stock size tires is a happy medium for a DD and working. You can search for sites that have calculators where you put in stuff like that and it will tell you what gear you're running. If anything if you want to know bad enough then take the diff cover off and count the teeth on both the ring and pinion gear, but you shouldn't have to go that far. Just do some searching for gear ratio calculators.

 

[1997chevydriver]

little update on this: I had a feeling that something wasnt quite right with my RPO code sticker when it told me I had the GT4 gear option. Sure enough I checked the VIN on the sticker and the VIN on the truck and they are different. Someone must have replaced the glove box at some point in the trucks life. Funny thing is the VIN in the glovebox decodes to 98 black 2 door tahoe just like I have. The only difference in the VINs is the production number at the end.

So now I have to figure out the gear ratio the old fashion way. I will do it when I do the blocks and torsion crank this weekend.

Im almost tempted to do 4.10s but I just drove 200 miles today and the gas gauge didnt move. My other 2 door would have drank a half a tank!!

FWIW, if I am doing 70mph my rpms re around 1700. I can do 80mph and still keep the rpms just under 2000. Im not sure if anyone here can guesstimate my gearing based off that but my 94 with 3.42s runs at 2,000 rpms at 70mph. Is there a possibility that I have 3.23s or even 3.08s in this ?

Sounds like 3.42s to me. I'll double check with mine tomorrow but I am almost positive I can run 75-80 right around 2k

 

[1997chevydriver]

Also what is your tire size

 

[BOTTLEDZ28]

Tire size is 265/75/16. My 94 has the same tire size with 3.42s in it and that ran about 2K RPM at 70 mph. This one runs a few hundred RPM under that on the same tire size.

 

[BOTTLEDZ28]

The difference in RPM between a 3.42 and a 3.73 is roughly 250 which dont seem like much of a difference but I guess it is.

 

[1997chevydriver]

Here is my truck with 265/75/16 tires and 3.42 gears.

You must be registered for see images

You must be registered for see images

You must be registered for see images attach

I didn't think these trucks came with anything under 3.42.

Only way to be sure what gears you have is pop the diff cover and look for a set of numbers stamped on the ring gear xx:xx mine is 12:41

 

[SkyHighColorado]

like this!

You must be registered for see images attach

 

[BOTTLEDZ28]

UPDATE:::

Well guys I got my power back!!!!!!!

I installed a K&N CAI kit, Magnaflow dual cat ypipe and a Gibson cat back exhaust and it woke the truck up very nicely. She now has the sack she should and sounds a little better at the same time. Im thinking the exhaust did more for the truck then the CAI but either way, Im happy with the results. Either the stock cats were getting clogged or the 2 gallons of water in the muffler!

 

[tylers88]

You must be registered for see images attach

FWIW this is my NBS with 5.3/4L60E and 4.10s when it had 265/70R17s on it, drove it on vacation, IA to SC going 75-85 the entire way and got about 17.5 overall