NEWB STUPIDITY!!!! REar diff. questions. SORRY!

[85runner]

I have a lifted 85 4 runner 4 by 4. The engine is rebuilt, but other than that, the drivetrain/diffs are stock.

ok guys. I already made two posts about my transfer case and rear diff. At first i was told the transfer case was bad, but now a mechanic looked at it and told me for sure that it is the rear diff.

Can someone simply explain how a rear diff works to me, and the parts that could go bad and can be replaced. I am still unsure what a "third member" is, and how much/ where i can get a "locker." i'm assuming a locker is just a posi, right?

My truck felt like the driveshaft u joint was bad. A thumping feel and sound was coming from underneeth. However, the driveshaft is good, and the rear diff is bad.

What exact part is going bad/grinding to make that noise/feeling? Can i replace it with an aftermarket/better part? The mechanic said it is not the two main gears in the pumkin, but the part that transfers the power from the driveshaft TO those gears. Please give me some info on the terminology, prices, and where to buy these parts needed to replace/upgrade my stock/busted rearend.

I can't justify paying 200 dollars to replace the rearend with another STOCK and USED rearend.

thanks!

Sorry for my newb stupidity!

 

[ToolmanJohn]

I don't know but...

Not really knowing anything about the insdie of the differential, $200 sounds wicked cheap in comparison to a buddys 1998 that he blew the rear end in his driveway. $1200... That's the price of not stopping before shifting and gunning it I guess.

 

[fourwd1]

"Third member" is just a term used for a "drop out" diff, meaning you can unbolt and remove the entire diff from the axle housing to work on it, instead of pulling a cover to work on it in the axle.

Simplified, the main things in a standard open diff are the ring and pinion gears, the carrier the ring gear bolts to, and bearings.

Basically, the pinion gear takes the rotation of the drive shaft and transfers it to the ring gear, which turns the axle shafts.

Go here and scroll down to "General Info"
http://www.ring-pinion.com/tech/techind.html
There are a number of things you should read.