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Meeky Moose

how do ya tell the difference??

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ok how would i figure out what differential and trans i have i this hatch? i mean as in open diff, locking diff, LSD, and gearing.. 3.70 or 3.90??

 

i know the rear diff is a 3.90 as it says on the tag, but doesn't say if its locking, open, or LSD..

 

the big one i'd really like to figure out is what the gearing in the trans and front diff are.. is there any way to find out?? its a D/R 4-speed too btw...

 

thanks

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The rear diff you have is open. LSD rear diffs are marked 'LSD' on the same tag that shows the gearing. All LSDs came as 3.7 rear diffs, with the possible exception of the XT6 with 5 spd Full Time 4wd. I have heard that some of them came with a 3.9 LSD, but I don't know if thats true.

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if the tag says 3.90 but does not say LSD in big letters, it would be open, unless the previous owner did the LSD conversion. Jack the rear up with both tires off the ground, and spin one. if the other goes in the same direction, it's an LSD. if opposite direction, Open.

 

front diff would obviously be a 3.90 also.

 

if it's a 83+ tranny with 9" clutch, 3rd and 4th gear will be slightly taller (than 82-) for better highway mileage.

 

the locking diff was an option available only in (I think) 87+ ea82's. (the full time 4wd ones) and it locked the center differential. your tranny does not have a center diff, so when you lock into 4WD, it's locked front to rear.

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that pretty much sums it up :D thanks..

 

on another note, i know when i drove it home the front diff was engaged as the linkage was adjusted backwards. so with shifter in 2wd the front was locked..

 

in 4th gear at 55 mph it ran at 3500 rpm's..

 

once i got it home and figured out the linkage problem and got it unlocked while in 2wd.

 

4th gear at 60-65 mph is only 2500 rpm's

 

i always thought when ya put it in 4h it was the same gearing as 2h only locked all 4 in... so i was a bit confused when the rpm's changed just by unlocking the front.. any of this make sense?

 

so needless to say since the speedo is off 10 mph cause of tires and lift, i never get it outa 3rd gear around here, and still don't get close to 4k rpm's...

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there is no gearing change from 2WD to 4HI.....

 

not sure what you mean about front locked? sounds like you were in 4WD....

 

front diff is open, and always used for 2WD. (transfers power to tranny axle stubs.

 

in 4hi, both front and rear diffs are open, the front rear are directly connected with no diff, so when you turn a tight corner in 4WD, you will get popping/binding due to the speed differences and no center diff...

 

in 4lo everything is the same, except the ouput ratio is lowered 1.45 approx.

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well the front lever on the trans, the one that the linkage bolts too and moves when you shift the 4wd lever..

 

 

when the lever was in 2wd that lever on the trans was all the way forward.. and it would not go into 4L at all..

 

in order to get it into 4L i adjusted the linkage so that front lever on the trans is in the back position when in 2wd..

 

so when you pull it into 4low it pushes the front lever into the forward position...

 

i'm wondering if since the shifter was in the 2wd position and the front lever was in the forawrd (4low position) if i drove it home 300 miles in 4L? or at least the front end in 4L and not turning the rear?

 

anyways, it was popping anytime i'd slow down and get off the highway, other than that it did great if it was in 4L for 300 miles :slobber:

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Sounds like you were indeed in 4 lo the whole time - at least by looking at your RPM data you were...

 

The owners manuals say to *never* go over 40 MPH in 4 lo, so I hope you didn't hurt anything. If you didn't go over 55, then you are probably fine. I have heard of people blowing tranny's by doing 75 in 4 lo tho, so it is possible.

 

GD

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4-speed

 

tranny seems fine to me, little hard shiftin into 3rd but that started when i had spiffy lube change the water in the trans to 90W

 

the right seal needs changed too, its drippin a little..

 

my speedo said 50-55, but the turbo wagon's speedo said 60-65..

 

so i'd say i got a tough tranny to take a 300 mile trip in 4L at 60-65 mph :lol:

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