Diff. Identity

Discussion in 'Technical' started by blugene, Jul 28, 2006.

  1. blugene

    blugene Senior member Supporting Member

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    So Where should I start? How can I tell what I have? I will be wanting different gears and will need some help with the whole process of choosing them and maybe installing them. I would rather buy a whole complete unit set up with the final decision in gears and such. This project is not imediately needed, but it will require attention soon after I get the car running. I see that the unit is leaking at the front area and if I am going to be doing ANYTHING to it I figure I might as well be prepaired and have what I will be needing. Thanks for your time :drink:
     
  2. boss9

    boss9 Member

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    If you're lucky there will be a tag on one of the differential bolts.
     
  3. blugene

    blugene Senior member Supporting Member

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    I couldn't really see one, but I will be crawling under there later tonight and i'll check for it then. Will I be able to tell or is it coded?
     
  4. ThisFords4U

    ThisFords4U Member

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    It should say the ratio on it. But if the tag is missing, put a block on both sides of the front wheels and jack up one of the rear wheels ( only one because you don't want the other to turn), and put the trans in neutral. Now, you might want a reference mark on the drive line/dif yolk, but you want to turn the wheel that is off the ground in one direction, and count how many times the driveshaft turns a complete revolution to the wheel turning 1 complete revolution.examples:

    if the tire turns 1 rev and the driveline turns slightly over 4 its 4.10
    slightly under 4 its 3.90
    3 3/4 its 3.73
    3 1/2 its 3.55

    and so onhope this helps

    Rob
     
  5. blugene

    blugene Senior member Supporting Member

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    [​IMG] Intresting... That sounds... Lazy, I'll do it!
    Thanks!:biglaugh: Be back in a few!!
     
  6. blugene

    blugene Senior member Supporting Member

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    This can't be good for those quick take offs, can it? I need some quickness, I need some gears, I need some advise, then... i'll need some money. Which now brings me to ask... how much am I looking at? Or, what can I find for say... $400.00? This is in my time frame of my personal dead line, any more, and i'll be into my new dead line. I don't want to wait another year, so let me hear some good news.:confused:
     

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  7. fan2488

    fan2488 Member

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    gene. try some swap meets. a lot of the one i go too will have some. they are already rebuilt and you have your choice of gears. ive seen some with a 3.55 for $325.00. just pull your old and put in the new. not a bad deal in my book.
     
  8. FishnRace

    FishnRace Jamie

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    blugene

    Tag decode from picture:
    Lower left number tells what gear and differential. 3.00 means what it says ... 3.00 gears. The decimal point means it is an open differential. If the decimal were replaced with an L (3L00), you would have a TRACTION-LOK differential ... but you don't :slap: .

    I too am looking for a rearend upgrade. There are a couple of places on eBAY that are selling complete 8" POSI third members for $600-700 :( with choice of gear ratio. I haven't inquired as to what brand of gears they are using(could be poor quality).

    If you rebuild yourself:
    8" Master rebuild kit is going for $75 on ebay
    8" posi rebuild clutches for a TRACTION-LOK (if you can find a used one) are going for about $60(?)
    Set of quality gears can be had for $150-200
    Don't know how much a used TRACTION-LOK differential will go for ($150-300?)

    Bottomline is $400 will limit what you can do unless you don't care about posi OR you are willing to run a mini-spool (Mini spools are only about $30), OR you find a GOOOOOOD deal.

    Jamie
     
  9. boss9

    boss9 Member

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    blugene, check out a place called Speedway Motors online. They have 8" replacement gears for $155.00.
    Darrel
     
  10. Scotty P

    Scotty P Member

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    I went with the Powertrax here are the parts and prices off my invoice I am holding:

    PWT 1810 LR Lock Unit $299.95
    RMG-6900641 4.11 Ring/pin $164.50
    RMG-8310151 bearings/instal kit $89.85

    My total cost was $$554.00 Been running it for a few months and love it. A bit noisy but over the flowmasters who can hear it! Scotty P
     
  11. igo1090

    igo1090 Member

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    shop around. i got my 4.10 gears on ebay for$85, mini spool for $45, installation kit for $55, & a guy i know installed them all for $75.
     
  12. ratio411

    ratio411 Member

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    Don't run a mini-spool on the street!
    Bad on parts and dangerous for us on the roads around you...
    They are made for dirt track use.

    Dave
     
  13. igo1090

    igo1090 Member

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    lets not start the mini-spool argument again. there are opinions both ways with key word being opinions. he can search several different threads to see the pros and cons, if he wants them.
     
  14. blugene

    blugene Senior member Supporting Member

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    I tried and came up with none. Got any search tips? Thanks
     
  15. igo1090

    igo1090 Member

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    go to the search at the top right of the page. type mini-spool. i did it and got about 30 threads to look at.

    essentially, since u are interested, some people feel that they are dangerous and shouldnt be used on the street. uncontrollable.

    some of us that use them feel they work really well, if you drive sanely. technically they arent legal at some drag strips. in lo hp applications they are fine.
     

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