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  1. #11

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    Quote Originally Posted by younggun View Post
    how to I check to see if I am dragging the front running gear? I know that when the truck moves so does the front drive shaft all the time, is this what you mean? it isnt actually in 4wd because in loose stone only the rear tires spin but I am intrigued as to why the transfer case seems to be turning the front drive shaft, not real familliar with these newer style 4x4 systems so I wasnt sure if that is normal or not.

    if ur drivershaft is spinning like the front wheels are engaged then they probly are, the hubs are supposed to unlock too, its normal for some driveshaft turning. just not like it is when its in 4 wheel. i take it u have a snappy throttle and all that and that u have cleaned all the carbon out of it, it all will help.

  2. #12

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    ok, i checked the 4wd over the weekend and it is definiately disengaging as it should. front Drive shaft turns freely in park while in 2 wd. so I am now leaning toward the converter and trans again, cant think of anything else mechanically that could be responsible for this much of a lack in low end power and the terrible fuel consumption. Going to try and get it to the trans shop this week that built my tranny for the 84. He says he can hook diagnostics to it and drive the truck to verify temps and operating characteristics to help pin point the problem if there is one to be found there.
    "always build it twice as strong as you think you will need":glasses:

    1984 Chevy k20-old blue
    1995 chevy k2500 workhorse
    2011 Honda Civic SI- because its the most fun you can have getting 27mpg!!!
    2005 Hemi Durango- the wife's go fast grocery getter!

  3. #13

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    Quote Originally Posted by younggun View Post
    ok, i checked the 4wd over the weekend and it is definiately disengaging as it should. front Drive shaft turns freely in park while in 2 wd. so I am now leaning toward the converter and trans again, cant think of anything else mechanically that could be responsible for this much of a lack in low end power and the terrible fuel consumption. Going to try and get it to the trans shop this week that built my tranny for the 84. He says he can hook diagnostics to it and drive the truck to verify temps and operating characteristics to help pin point the problem if there is one to be found there.



    did u try with the engine running cause alot of time when the vacuum isn't present it acts normal or if its electric it will do the same thing, act normal. it still wouldn't hurt to let a trans shop check it out eitherl. i take it u have ran a can of the b-12 chemtool thru it already. the carbon will starve the engine and make it run harder, that is always the 1st thing i try and it clears alot of things up, just that it cleans out all the gunk that builds ups, and increases throttle response.

    don't know if any of this helps, its always worked for me, so when u do find out whats up please let me know. by doing all that cheap stuff 1st i have cleared up alot of things. also by it being a 2500 it could have a lower gear, and u might want to check the grease in the housing also. i always go cheapest first, i wish u the best.
    Last edited by HippyD; 02-08-2012 at 06:36 AM.

  4. #14

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    Check for a vacuum leak, Take an oxy acetylene torch and set up a nice hot cutting flame and blow it out with a air nozzle. Then, start the truck and move the gas around the throttle body, all the hoses and tube which carry air or vacuum. If the truck changes pitch, then you have found a problem. What is the fuel pressure? Should be 60 and 65 when you goose it.

  5. #15

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    Have you put a timing light on it? I just junked my 93 2500 HD 4x4 4:10 geared plow truck. A great truck for the 16 years I owned it, but died from rust in the end. At one point I had similar issues and wound up putting a distributor in it due to wear on the gear. I had to replace all of the vacuum lines around 2000 as well due to dry cracking. Other than that I got 14 mpg town or highway.
    Last edited by Still Creekin'; 02-09-2012 at 06:40 PM.

  6. #16

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    Thanks for all the responses and input, To answer a few of you yes we have checked the timing (with the ignition wire under the dash unplugged as required) It is good 0-1 degree. We did a complete vacuum check on the truck at the shop and everything tested ok there. The truck was running when I checked the 4x4 to make sure it was disengaging.

    Now for the kicker I spoke to another mechanic yesterday and explained what all I have done and how the truck was acting he then said "change the coolant temp sensor", and I said only reason I haven't is because it has been tested by 2 shops and it passed both times. He said "tests aren't always 100% on these computerized sensors and such" so i bought an $11 sensor popped it in and so far the truck runs 100% better so I am anxious to check my mileage in a day or two and see if it begins to improve as well. Thanks again for all the help, I will post the results as soon as I get some.

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