Are older S10s geared lower?

[Ducaire]

I have a 1990, extended cab, Chevi (Tahoe) S10 with a 4.3 Liter engine. It seems to have a good bit of power until I get above 60 mph., and then I have to start giving it the gas. I've heard that older pickups are geared for towing and hauling. My truck will probably run about 85 mph., and then it runs out of gear. (I have an automatic) Is it possible to have my transmission adjusted for running at higher top-end speeds? I never tow, so it doesn't matter if I lose towing power.

[rlith]

The gearing is based on your rear... Typically they came with 3:42 or 3:73, some even came with 4:11... To find out how high you're geared, look at the label in the glove box. Here are your RPO codes. Look for the one that starts with GU... (gu6, gu8, etc..) Let me know what it is and I can tell you how you're geared. If you're geared high (3:73 or 4:11) You can easily drop it down to 3:42 just by swapping out the rear (or the gearing in your existing rear diff) If you're running 4x4 and not 2wd, you would also need to redo your front diff. Post the RPO code for me..

Note: If your label is too faded, call your local GM dealer's parts department. Give them the last 9 digits of your VIN number, and they can tell you which gearing you have.

[NaKeDZX]

There's no reason your S10 shouldn't be able to get to the 100mph cut out.(not that you want to do 100 in an S10). Sounds like your cat might be getting clogged up or something. Unless you're actually at redline at 85mph (I doubt it), there's something bogging the engine down. And it's not the gearing.

[smokey041369]

just a added note for the gearing in the 4x4 s-10's if you change the rear and front pig gearing you also have to change the transfer case gearing. not doing the transfer case gearing you can do damage to it or to the tail end of the tranny. my buddy just went through this problem with his 92 4x4

[PurpleBeast94]

Originally Posted by NaKeDZX

There's no reason your S10 shouldn't be able to get to the 100mph cut out.(not that you want to do 100 in an S10). Sounds like your cat might be getting clogged up or something. Unless you're actually at redline at 85mph (I doubt it), there's something bogging the engine down. And it's not the gearing.

I have a 94 2wd 2.2 manual tranny and when i get onto the parkway, my rig seems to hit high rpms when i go anything above 65 mph. if im doin 85, the needle pinned, its really high and workin hard. i dont ever remember the truck doing this when we first got (new in 94 - 5yrs old) it so i dont think its normal for it. and how much would it be to get a new rear to allow higher speeds?

PurpleBeast94

[NaKeDZX]

Gearing on a vehicle is static, rpms at a given speed do not change as a vehicle ages or wears. Now, if you're clutch is slipping like mad a high speeds it's not going to last very long at all. When you say it's pinned, is the tach redlined at 85mph??? You know it's a 5 speed, right? LOL

I'm not sure how the 4cyl trucks are geared, but a 4.3 should have no problem hitting 100mph and should cruise between 2 & 3k on the highway. I've got the 3.73 gear and I think it runs between 2 & 2.5k@65mph.

Edit: After thinking about it, a 2.2 probably is pretty tapped out by 85-90mph. Changing the rear gearing for lower rpm on the highway is possible, but it'll hurt accelleration.

[Jerry80871852]

I had a 85 S-10 Blazer 4 X4, I think the engine was a 3.8, not sure, but it was the one below the 4.3.

It had 5 speed Manuel and 85 MPH was all it would do on straight flat highway, it did not have no power at all, on a down hill run it might would have gone faster if you got out and pushed.

My 92 S-10 4 x 4 with the Votec 4.3 with automatic will peg the speedometer out.
May God Bless,
Jerry

[troy1]

smokey why would you change the transfer case? the only gearing in the is the reduction for low range other than that what comes out of the back of the trans is what comes out the the transfer case in 4Hi & 2Hi. there is no gearing when in those two modes.

[chcknugget]

Originally Posted by troy1

smokey why would you change the transfer case? the only gearing in the is the reduction for low range other than that what comes out of the back of the trans is what comes out the the transfer case in 4Hi & 2Hi. there is no gearing when in those two modes.

Yeah, do you know of anyone successfully swapping different gears?

I would sorta like to know what's involved.

[rlith]

Originally Posted by chcknugget

Yeah, do you know of anyone successfully swapping different gears?

I would sorta like to know what's involved.

Easiest is swap out the entire rear, but to use your existing rear, it's a matter of changing out your ring gear and carrier

[chcknugget]

Originally Posted by rlith

Easiest is swap out the entire rear, but to use your existing rear, it's a matter of changing out your ring gear and carrier

I'm sorry I meant swapping the gears on a 4wd. rlith, is yours 4wd? And if it is, did you swap the fronts?

[rlith]

To regear a 4wd, then yes, you have to re-gear or replace the front diff with the same gearing as the rear

[J-Ri]

I've got a 93 4.3L, it will go pretty damn fast. I was cruising down the highway well over the top of the spedometer. When I let off the gas, it took 10-15 seconds to coast down to 85. Those of you that can't go over a specific speed either have an exhaust restriction or a clogged intake.

[Jerry80871852]

Please remember the smaller V-6's do not have the power of the 4.3, so if the power is not there it will not do as your 4.3 does nor mine 92 S-10 Blazer with the Votec 4.3.

Also had a 1985 full size Chevy pickup, with the 4.3 and a 4 barrel carb., it did not have the power to pass someone on the open highway, but when you kept your foot in it, it consumed much gas, but it would not reach 90 MPH, to much truck and wind resitance for this motor.

The 4 barrel sound good when you steped into it, but the result of stepping into it were not much.

[dmbrisket 51]

Originally Posted by J-Ri

I've got a 93 4.3L, it will go pretty damn fast. I was cruising down the highway well over the top of the spedometer. When I let off the gas, it took 10-15 seconds to coast down to 85. Those of you that can't go over a specific speed either have an exhaust restriction or a clogged intake.

or we have rev/speed limiters on all 96 and newer vehicals, otherwise i would berry it out at 100, i have a shift at 75 i beleve, so it gets there quite easyly