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Overdrive Questions

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by Lazydog, May 12, 2003.

  1. Lazydog

    Lazydog 1/2 ton status

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    I love my truck but the gas mileage is killing me. I also own a 89 Nissan Sentra that I hate. I don't want to sell the truck but I may have to. Anyone know of any overdrive units I can run to get better mileage? It's a 4spd, 205 truck. Thanks.
     
  2. sled_dog

    sled_dog 1 ton status

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    I could be way wrong but you may spend as much if not a little less on an overdrive unit as you would to get say an NV4500 and upgrade to a 5 speed with overdrive and creeper gear. If I could afford to I would be running an NV4500 right now.
     
  3. 2Dogs

    2Dogs 1/2 ton status Premium Member

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    What is it now and what would an acceptable MPG be?

    If you are looking for 18 or better you probably are going to throw money at an impossible target.
     
  4. dyeager535

    dyeager535 1 ton status Premium Member

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    Unless someone drops an OD unit in your lap (IE Gear Vendors, NV4500, etc.) you will spend way more money putting in OD than you will recoup (in a typical vehicle lifetime) from saving gas with those units. If you can't afford the gas now, you can't afford to put in OD.

    If you get 20MPG with a gas powered Non-OD carbed truck, you can consider yourself lucky, but don't expect ANY to get much higher than that. And I'm willing to bet vs. the Sentra, even 20MPG is shoddy.

    Simple fact is, these trucks aren't good commute rigs if you can't afford the gas. Sorry to say it, but you gotta drive the sentra if you want to save on gas. Why can't you just stop driving the truck so often? Or sell the Nissan and buy something else that gets good mileage that you like better? (which I know, isn't possible : )
     
  5. HarryH3

    HarryH3 1 ton status Author

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    Sell the Nissan and use the money for gas. /forums/images/graemlins/wink.gif Seriously, you can spend a LOT of money to add some type of overdrive, but it will typically only add 1-2 MPG. It would take a pretty long time to break-even on paying for the overdrive. /forums/images/graemlins/frown.gif
     
  6. SUBFAN

    SUBFAN 1/2 ton status

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    If your not happy with the mileage now, wait til you change the gears, lift it, put on bigger tires, and really make it an 'aerodynamic' nightmare!!!!!

    (Look for a Cummins TD and swap that running gear in and make the rest of us jealous with your mileage and torque.) /forums/images/graemlins/grin.gif
     
  7. sled_dog

    sled_dog 1 ton status

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    yeah I am constantly jealous of my buddy with his 1994 2500 Dodge. 12V 5.9 cummins with stacks, NV4500, and fuel pump upgrade. So much torque the stock clutch isn't taking it. Walks away from my slow K5 like its standing still. My mom's car that runs a 15.9 on the GTech in the 1/4 mile loses to that thing. Oh adn he gets close to 18mpg, with like 32.5s.
     
  8. 88Silverado

    88Silverado 1/2 ton status

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    Hey...I have a stock 88 with TBI and Overdrive with 3.73 and 32" tires. I get.......................10mpg in town and 12 on the highway /forums/images/graemlins/frown.gif These trucks just dont get good mileage.
     
  9. SUBFAN

    SUBFAN 1/2 ton status

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    If I won the lottery.... /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif
     
  10. georgiared84

    georgiared84 1/2 ton status

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    What kind of mileage exactly are you looking for? I just dropped a brand new 350, new carb, mild cam, into an 84 with a np208 and 700r4. On the highway it might get 15 mpg on a good day, but around town you're still looking at about 11 or 12 at the most. If you're looking for a fullsize with good gas mileage the k5 just isn't the one. You might as well go with a 2 wd shortbed pickup and save a couple thousand pounds.
     
  11. Lazydog

    Lazydog 1/2 ton status

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    Thanks for the posts everyone. I'm getting 10-11mpg average. I'm just grasping at straws, and I hate the Nissan(wifes old car). I'm thinking about sucking up the mileage and keeping the truck. I just fixed the centrifugal advance(the weights were stuck) and now it runs great. That should definately improve mileage. I thought of the NV4500 but I don't have the right Transfer case. I figured the "right" NP208, or a conversion to the 205 I have, would be expensive as well. Poor mans delima. Unless I use the proceeds from the sale of the Nissan toward the 5spd trans. Hmm, now I'm thinking Thanks again.
     

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