Rear axle

[Anonymous]

Hey, when my brother and i was out testing the -68 today we saw that it made 2 nice burnout tracks. Back home we raised it and rolled the wheels, both wheels spin in same direction and it seems like the rear axle is "diffed" (swedish, dunno english name, could it be "traction lock"?)

Anyway when i check the rear axle housing i can't seem to find any codes on it, i just see a tag showing "902", can any of you tell me where i check the coding and how to make sure exactly what kind of axle i got. The housing is bolted with 8 bolts, it got 4-lug wheels on...

 

[Anonymous]

Well, if you roll the tires and they both go in the SAME direction, that means its not a limited-slip, but it might be open (but I'm not totally sure about that one). Not quite sure what diffed means.

As far as the codes go its all in your door tag VIN, take that and type it into a VIN decoder like such and that should give you the information you need.

http://www.fomoco.com/mustang-vin-decoder.shtml

 

[Anonymous]

Thx, i've checked the VIN, but i am pretty sure the driveline has been changed during the years. I have a gutfeeling that some guy put a V8 in my car at some time but didn't get the build approved by authorities.

Shouldn't there be a place where you find a code on the axle housing? All i find is this plate fastened under one of the bolts which says "902" - doesn't make any sense to me, all info i find in my manuals says that coding should be somthing like "WDZ-XXX" or something.

 

[StrangeRanger]

No! No!
With a limited slip or a locker when you jack the rear up, put the tranny in neutral and turn a tire, the opposite tire will rotate in the SAME direction. With an open diff, it will rotate in the opposite direction.

There is nothing in the VIN code about type of diff.

 

[Fred]

The difinitive test is this: jack up the car, put the tranny in gear, try to spin one rear wheel. If the other wheel will spin the other direction you have an open diff. If the wheel will not rotate you have a locking, posi, limited slip, or whatever the technical term for your specific axle is. Or your brakes are too tight. Or something is broken. Or the spider gears have been welded.

 

[Anonymous]

Ok, thx alot for yer answers. I will check tomorrow if the wheels spin in same direction or opposite. However i get 2 tracks when burning rubber, isn't that a tell that the diff is locked to spin both wheels? If not, what is the difference... (newbie warning, ok :roll: )

The question still remains though if there are some marking on the axle housing which tells me some coding that i can check up. And what is this "902"-marking?

 

[Anonymous]

The data plate will contain the axle code as it was originally equipped. I believe the axle had a stamped tag affixed to one of the bolts. If it is missing, you are left with counting bolts holes and comparing housing shape, and gasket shapes to drawings. I do not know if a limited slip was available on the small 4 lug axles. This site has some info on identifying 9" & 8" Ford Axles.

http://www.gearheadracing.com/RefLibrar ... Differ.htm

Doug

 

['61 Draggin Wagon]

If it was originally equipped with a locking differential, the VIN plate would show a letter for the the axle code. If not a locker, the axle code would be a number. Ford used this for years.....
Other than that, you'd need to pull the cover & take a peak.
The bolts are on the backside of the differential, holding a cover on? Or are the bolts on the front side?
You can also check ratio while the rear wheels are off the ground, by counting how many times the driveshaft needs to rotate to turn the wheels one revolution.
Hope this helps,
Darryl

 

[48fordnut]

By leaving tracks for both tires on the pavement, you have established that in fact it is a limited slip.

 

[Kstang]

no, I left some tracks with my mustang which i know has an open diff, and it left both tracks. Some times if you hit it just right, they will both start slipping and leave marks.

 

['61 Draggin Wagon]

Or if the rear end is about to puke, it'll pull posi burnouts.... AMHIK
Darryl

 

[hasa68mustang]

mine switches occasionally... sometimes the right will turn sometimes the left and sometimes both... I think its confused.... in reverse both always spin.. is that safe?

 

[Anonymous]

in an open differential the power turns the side with least resistance.

So picture this you are going up a hill on a icy road, and there is a patch of ice coming up to your right rear tire. if the tire keeps spinning you know it's either a worn out ls or a open differential. If the car kicks side ways or your left rear wheel starts spinning you know you have a working ls or locker.

The reason why open differential spin 1 wheel sometimes, then both others is because, where you are driving it and how you are driving it. Say you are going on a wet road and jam on it around a corner, the wheel furthest from the inside of the curve will spin before the wheel closest to the inside of the curve. Then again thats mostly because, of where your weight is being distributed at that point in time but, since the weight would be on the front of the car and to whichever wheel closest to the inside of the curve you would have less resistance on your other wheel furthest from the inside of the curve

This is also why most people with open diffs usually only spin 1 tire while powerbraking. Usually 1 side brakes just a little harder or your wheel bearings are going out or such. so the better side will spin and the side with worn out bearings or stickier brakes will just sit there.

 

[Kstang]

Heck when i did it i was on the flat ground, and kinda pissed off! just let it rip and both started spinning, could they both had an equal amount of resistance? who knows. I just know an open will spin both. I have seen some video's of people doing a one wheel wonder at the track, with some friends grabbing the rear end and pushing it up and down and the other wheel will start spinning?

 

[Anonymous]

That doesnt sound safe