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PROVE SUBIEJIM WRONG!!! RX discussion!


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The Rx tranny is just a D/R with a locking center diff and that is just what it is , it just has a set of spider gears on the rear out put shaft like some of the EJ trannys and but no clutches , if you lock the front brakes with the Ebrake you will do a rear drive burn out but i would not recomend it , and with the diff unlocked it is full time giving power to the tires with the least traction ,yes i said the least if you get one tire off the ground it will go no ware , trust me i have one all apart in my shop , they are not a good off road tranny beacuse they are a 3.70 with a 500 rpm drop low range .

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alright i just got back from whistler so i can post our outcomes... while me and Jim's observations are the same, we have yet to actually come to a conclusion...

 

 

at first when we put the clutch disc on and started spinning it the rear output didn't budge... which got my mind going, "BAH!"

 

but it HAS been sitting for 4 or so years... and it free'd up after a little movement...

 

now what we did is we locked one of the front driveshafts and left the other open with an axle cup left on it for some leverage...

 

now that i think about it after loosening up the gears we should have unlocked the front axle we had locked and see if all the outputs spun without interference...

 

also... when he had the driveshaft in the rear and got me to spin the clutch disc i couldn't hold onto the cup without it spinning and not very much power was being sent to the rear... mind you i dunno how hard jim was squeezing the shaft... (i assume none or very little?)

 

now that i think about it perhaps the reason i was having such a hard time holding onto the cup while spinning the clutch disc is because the rear output shaft hasn't gone through a diff yet... meaning there was 3.7x more torque going to me then to him...?

 

i dunno... we've yet to draw any conclusions really... he still believes its a 2wd trans... i guess only getting one into the car and actually trying it out will give the best idea of how much power actually goes to the back...

 

more tests!:-p (or we could just leave it be... i'll run full-time 4wd and he can keep playing with the part-times...:rolleyes:)

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Power flow in an AWD and Fulltime 4WD box goes like this: lets assume 5th gear as in the above posted picture from the FSM

 

1 flywheel to clutch disk

2 clutch to input shaft

3 input shaft to dual-range gear set, if dual range

4 input shaft to 5th gear set

5 5th gear set to output shaft

6 output shaft to pinion shaft of center diff.

7 spider gear of center diff to one to one gear driving input to rear prop. shaft prop shaft to rear diff

7 spider gear of center diff to drive pinion of front diff

8 front diff spiders to left and right front half shafts

8 rear diff spiders to left and right rear half shafts

 

I've used the same number to denote events that happen simultaneously under ideal grip conditions

 

What confuses many people is that the front diff pinion shaft passes right through the main output shaft of the gear set thus at a casual glance it looks just like the output shaft/pinion drive combo of a part time or FWD gear box, the output shaft of the gear set rides on roller bearings on the front drive pinion shaft and this is it's only path of contact between the two other than through the center diff.

 

Now because the front drive section of a full time box has more drag resistance because the output shaft is literally rotating around it on bearings and the front diff as well. If one puts it in gear and turns the input shaft by hand the torque will go the path of least resistance which is usually out the rear stub shaft, what you will notice is that if the front stubs aren't turning and the rear stub is turning that it will be turning twice as fast as the gear ratios say it should, proof that the torque is going through a differential with one spider not rotating..

 

hope that clears it all up..forgive me for errors; it's late,

 

Kaz

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Now because the front drive section of a full time box has more drag resistance because the output shaft is literally rotating around it on bearings and the front diff as well. If one puts it in gear and turns the input shaft by hand the torque will go the path of least resistance which is usually out the rear stub shaft, what you will notice is that if the front stubs aren't turning and the rear stub is turning that it will be turning twice as fast as the gear ratios say it should, proof that the torque is going through a differential with one spider not rotating..

 

we observed the opposite of that... the rear output shaft was having a much harder time spinning then the axle stubs on the front... mind you after we free'd it up a bit the one front unlocked axle stub was spinning with the rear output... and shouldn't the rear spin 3.7 times faster then front axle stub?

 

hence the gear ratio in the diffs???

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