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Discussion Starter #1
I went on the amsoil website so I can order the fluid and whatnot for my diffs, tranny and transfer case and after I put in my info, it gave me about 100 different combos. I have a 2008 Dodge 3500 6.7 TD 4x4 Megacab auto. What rear end and front end diffs do I have. I'm pretty sure my tranny is a 68rfe but when I started looking for the tranny filter and all that jazz same thing. Does anyone know forsure exactly what I need for filters and oil? Thanks
 

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Front = AAM 9.25"
Rear = AAM 11.5"
 

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Discussion Starter #3
now one says anti and one says open, the difference is one takes more fluid.
 

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anti = anti-spin (limited-slip differential)
open = open diff (only 1 tire spins)

Do you know if you have factory limited-slip or not?
 

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Discussion Starter #5
i'm not sure, how would i find out?
 

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Discussion Starter #6
I can't ever remembering spinning and only 1 tire spun, i'm pretty sure the rears always spin together. when I'm in 4 wheel and turning she jumps and jerks pretty hard so I'm assuming my front isn't open either then
 

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You probably have front and rear limited slip diffs. Call Chrysler or your local dealership and give them your VIN number and ask them if it says it has LSD's or open diffs. They can tell you.

Or, if you bought your truck brand new you can look on the window sticker that lists the options.
 

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Discussion Starter #8
yeah I think the window sticker is in the glove box, I will have my wife look.
 

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There's no LSD option for the front. The bucking and chucking in 4wd is because the front and rear driveshafts are locked together and must spin at the same speed. Has nothing to do with the diffs.
 
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There's no LSD option for the front. The bucking and chucking in 4wd is because the front and rear driveshafts are locked together and must spin at the same speed. Has nothing to do with the diffs.
Well, my truck sure isn't open diff in the front.......If it's not open, then what is it? And no, I haven't swapped anything in it.
 

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Well, my truck sure isn't open diff in the front.......If it's not open, then what is it? And no, I haven't swapped anything in it.
How are you determining your front diff isn't open? Have you opened the diff up and looked inside?
 

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No, both front tires spin evenly under stress.
 

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No, both front tires spin evenly under stress.
All that tells you is that:

a) You're applying enough torque to overcome the friction of both tires
b) You're not getting much traction

With equal traction from both tires you'll spin both at the same time with an open diff, an open diff sends equal torque to both sides. If you're getting on the throttle good (Looks like you like mud) then it's not very hard to overcome the traction of both tires even with an open diff.

There's a really easy way to determine if you have an open diff up front and it doesn't involve opening it up. Just jack both front tires off the ground and spin one of the tires. If the tire on the opposite side rotates the opposite direction then you have an open diff. If it rotates the same direction then you have a limited slip.

But, if you bought the truck new or it was stock when you bought it then you have an open front diff, no question about it. The only Ram that has any traction aid in the front from the factory is the Power Wagon, there was simply no option for it on standard Ram trucks. The only option is for the rear.
 

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All that tells you is that:

a) You're applying enough torque to overcome the friction of both tires
b) You're not getting much traction

With equal traction from both tires you'll spin both at the same time with an open diff, an open diff sends equal torque to both sides. If you're getting on the throttle good (Looks like you like mud) then it's not very hard to overcome the traction of both tires even with an open diff.

There's a really easy way to determine if you have an open diff up front and it doesn't involve opening it up. Just jack both front tires off the ground and spin one of the tires. If the tire on the opposite side rotates the opposite direction then you have an open diff. If it rotates the same direction then you have a limited slip.

But, if you bought the truck new or it was stock when you bought it then you have an open front diff, no question about it. The only Ram that has any traction aid in the front from the factory is the Power Wagon, there was simply no option for it on standard Ram trucks. The only option is for the rear.
I get equal traction all the time. Through everything I've put my truck up against. Not sure why if they don't offer an LSD in teh front, but my steering is awefully snatchy for a "non-LSD" front....On flat dirt it digs 4-even holes with all 4 tires at the same time. Mud and red clay....pulls both tires even if one is in a rut and the other is on the high-ground. I just find it strange. Might be open, but I've never seen an open diff act like a locked diff when in 4-wheel drive. My experience with open diffs is only 1 side spins, the end. Guess they've advanced these trac-control alot. Sooner or later I'll probably end up chunking this 9.25 for a Dynatrac Dana 60 with a full-Detroit locker and Dynatrac free-spin kit, and throw a full-Detroit locker in the back, too.
 

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I get equal traction all the time. Through everything I've put my truck up against. Not sure why if they don't offer an LSD in teh front, but my steering is awefully snatchy for a "non-LSD" front....On flat dirt it digs 4-even holes with all 4 tires at the same time. Mud and red clay....pulls both tires even if one is in a rut and the other is on the high-ground. I just find it strange. Might be open, but I've never seen an open diff act like a locked diff when in 4-wheel drive. My experience with open diffs is only 1 side spins, the end. Guess they've advanced these trac-control alot. Sooner or later I'll probably end up chunking this 9.25 for a Dynatrac Dana 60 with a full-Detroit locker and Dynatrac free-spin kit, and throw a full-Detroit locker in the back, too.
Could be the weight of the Cummins on the front is what's doing it, the engine is a pig and would take a bit of torque to break the fronts loose.

I know I'm open in the front and my truck is the best 4wd I've had, short of a Jeep built for rock crawling. Even in the snow it's insane how much traction I have in 4wd. I think it's just the weight that does it. If I didn't know any better I would've said my truck had a traction aid in the front diff, too. :)
 

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Definitely an open diff. Yahoolagin mentioned it already, "The only Ram that has any traction aid in the front from the factory is the Power Wagon, there was simply no option for it on standard Ram trucks. The only option is for the rear."
If it were a used truck, there would be the possibility that the previous owner added something. Try this: Find a trench of some kind off the side of a dirt road or offroad...in a safe place. Should be about 2-3' deep and only about 6' wide. Staddle the trench diagonally and blurp the gas "Go and stop" at a slow speed and look to see if the dropped out tire spins and tills up some soil. You just need to break the tires loose, nothing more to see this. Or ou could just try some more Legal offroad activities that are more technical. After a couple trip you would know for sure. Plus side to that is you get to go wheeling for science...or something:thumbsup: If it doesn't grab or show signs of being "Driven", its open.
 

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Discussion Starter #17
no it is stock and I bought it brand new, so I definately have an open front, now I will just have to look at my window sticker to see if what I have for a rear.
 

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no it is stock and I bought it brand new, so I definately have an open front, now I will just have to look at my window sticker to see if what I have for a rear.
What I found out when I bought my 2010 crew cab 2500 is that the factory LSD rear axle was an option on the 2500, but was STANDARD on the 3500.

I doubt the running gear changed between 2008 and 2010. Since you mentioned that you have a mega cab dually, that tells me you have 3500, so chances are pretty good you have a factory LSD in your 11.5" AAM rear axle.

(I wish I would have insisted on that option for my 2500, my rear axle keeps breaking free on the wet washington roads.)
 

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What I found out when I bought my 2010 crew cab 2500 is that the factory LSD rear axle was an option on the 2500, but was STANDARD on the 3500.

I doubt the running gear changed between 2008 and 2010. Since you mentioned that you have a mega cab dually, that tells me you have 3500, so chances are pretty good you have a factory LSD in your 11.5" AAM rear axle.

(I wish I would have insisted on that option for my 2500, my rear axle keeps breaking free on the wet washington roads.)

I lucked out and got a ALS in my rear axle. Not sure what package you have to buy to get the ALS rear. Maybe it was simply a stand alone option...don't know? I do like it, but am used to an electric locker on all my Toyotas. I really liked the locker and it gave you that extra little something to get you places you would never have thought possible.
 

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Discussion Starter #20
Well my wife sent me a picture of the window sticker...I do have the "anti-spin differential rear axle" which was a $325 option. I also have the 68RFE tranny. It also says I have the 9.25 front axle with the hub extensions...so it really doesn't say anything else about that. So there ya have it, now I just got to find the best fluids and filters, the best deal on those things, and place my order. Any ideas?
 
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