Does RP owe me a new rear?

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The Trac-Loc used in the Corp 9.25 is a plate-type LSD...the thing that kills them is the clips that hold things together fall out. Again, this is a known common failure.

They are different from the Trac-Loc used in the Dana units (a two piece design) and vastly different from the Trac-Rite used in the AAMs (different manufacturer). I've rebuilt the single piece D60 Trac-Locs and two piece D80 Trac-Locs, and a similar type deal the D70 Power-Loc. The single piece Trac-Locs are a good design, but I think they got a batch of bad components.
 
Originally Posted By: 2010_FX4
Originally Posted By: dparm
I do know that Ford sells a friction modifier.

Quite right; Ford changed mine at 13,300 in my FX4 and although I had them use the synthetic MC fluid, they still added the modifier.
That's because Motorcraft diff lube doesn't have the FM built in like some other brands.
 
Originally Posted By: silentasknight
In my maintenance schedule in the owners manual it does not even tell you to change the gear oil. No wonder so many ppl are buying [censored] cars nowadays, so sad.


Ford says the same thing, in the manual for both of my cars. The rear end fluid doesnt need to be changed for the life of the vehical use the rear end was completly submerged under water.
 
No gear oil is good for 75-100K or lifetime I don't care what any car mfg or fluid mfg claims.
 
Why not just email RP your complaint and see what they say?

What do you got to loose?

Let us know if you get a response.
 
Originally Posted By: MarkM66
Why not just email RP your complaint and see what they say?

What do you got to loose?

Dignity.
 
"Dignity."

+1 exactly. Don't go beggin' for a freebie you know you don't deserve. It's not fair to companies out there that are trying to stand by their products.

I'm no RP fan but I can't believe that it could cause this kind of failure in a properly designed application. Perhaps the new oil with its superior lubricity allowed the clips to fall out of place? But then again, it's still not the oil's fault that it's slippery. It's supposed to be.

"$1,500.00 to rebuild a nine and a quarter was a ripoff, IMO."

Yeah, I thought that was steep, too. Not sure what a fair price for this application would be, though.
 
I have a 2006 Dodge 2500 and it states to change the rear end oil every 15,000 miles, its 4x4, so this gets very expensive(x2) and it is to only use synthetic 75w90. I have the lifetime warranty, so I will do it. Especially since I tow , sometimes over 10,000 lbs. But that is totally crazy to me. Big trucks call for 250,000 miles on synthetic rear-end grease and are under alot more stress, especially tri-axles. The first time I changed it was 500 miles, and it was a awful gray/mettalic color. Looked terrible. Ever since, I have used Mobil 1 and Royal Purple, both looked like new when they came out after 15,000 miles, like Kayro syrup. Its currently on a fill of Amsoil 75w90. At 15,000 miles, I put in whatever I get a good price on and thats synthetic. Its stupid to change it that often, in my opinion.
 
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If you read the manual closer, the 15k is for towing and severe duty...there is no change schedule for normal driving.

I have a similar truck, and ran one fill of RP 85w140 for well over 100k...there was nothing on the magnet of consequence. That rear has 245k on it currently, and just did 2500 miles towing 8500 pounds!

As for cost to rebuild that 9.25 corp, it cost me $800 back in 98 at a Dodge dealer. They have a "kit" that basically includes all the replaceable parts. I rebuilt it myself a second time (the dealer screwed up)...cost me $125 in bearings and seals plus the cost of the "spanner tool".
 
Unless you're towing in 4wd, no need to over maintain that front end.

If you want to reduce the severe service intervals, increase the fluid capacity and cooling of your 'end.

Never compare a common civilian vehicle with industrial vehicles. Its not stupid to over maintain an under engineered lowest cost component that barely makes the grade. Swap in a couple 2.5 or 5 ton axles if you don't want the 15k change interval.
 
Originally Posted By: Panzerman
I have a 2006 Dodge 2500 and it states to change the rear end oil every 15,000 miles, its 4x4, so this gets very expensive(x2) and it is to only use synthetic 75w90. I have the lifetime warranty, so I will do it. Especially since I tow , sometimes over 10,000 lbs. But that is totally crazy to me. Big trucks call for 250,000 miles on synthetic rear-end grease and are under alot more stress, especially tri-axles. The first time I changed it was 500 miles, and it was a awful gray/mettalic color. Looked terrible. Ever since, I have used Mobil 1 and Royal Purple, both looked like new when they came out after 15,000 miles, like Kayro syrup. Its currently on a fill of Amsoil 75w90. At 15,000 miles, I put in whatever I get a good price on and thats synthetic. Its stupid to change it that often, in my opinion.


Just for fun I looked up the Severe Service diff fluid change for my Expedition and an F-250. Expedition is 60,000 miles, F-250 with the Diesel is 95,000 miles.

Wonder why Dodge's frequency is so much higher?
 
Originally Posted By: OVERK1LL

Wonder why Dodge's frequency is so much higher?




This has been debated for years on the Dodge forums...the SAME differential used in a very similar product (a Chevy 2500HD/3500) has a much longer OCI than the Dodge. A lot of owners think the printed interval is a mistake, that it was an initial 15k change that they forgot to make the distinction for a longer interval afterwords.
 
Originally Posted By: Panzerman
I have a 2006 Dodge 2500 and it states to change the rear end oil every 15,000 miles, its 4x4, so this gets very expensive(x2) and it is to only use synthetic 75w90. I have the lifetime warranty, so I will do it. Especially since I tow , sometimes over 10,000 lbs. But that is totally crazy to me. Big trucks call for 250,000 miles on synthetic rear-end grease and are under alot more stress, especially tri-axles. The first time I changed it was 500 miles, and it was a awful gray/mettalic color. Looked terrible. Ever since, I have used Mobil 1 and Royal Purple, both looked like new when they came out after 15,000 miles, like Kayro syrup. Its currently on a fill of Amsoil 75w90. At 15,000 miles, I put in whatever I get a good price on and thats synthetic. Its stupid to change it that often, in my opinion.


The OTR trucks have a much larger fluid capacity in the differential, and many have temperature gauges to alert the driver if the operating temperature gets too high.

I agree that the 15k change interval is probably excessive, but considering your warranty coverage...I would buy a pail of 75w90 from your local oil jobber and change it as instructed.
 
I know its overkill. But I am sure being a 3/4 ton and Dodge figuring it is used for towing.Let a rear end exploded and your not be going by that stupid 15,000 mile rule and they would try to opt out on coverage. I read the manual closely, because I think 15,000 miles is crazy. Its sort of like the severe service oil changes. Unless you are a mail courier running from the east coast to the west coast only in the fall and the spring. You are in their SEVERE service category.
 
That's a pretty darn frequent OCI. IIRC, my Jeep says change every 30k for front and rear diffs. However, neither was done until I bought it at 100k. Front was making some gear noises under load from the lube being so shot, rear was still quiet. Both fluids came out black and nasty looking (and smelling), but no metallic bits, so no damage done, I think.
 
Originally Posted By: Panzerman
I know its overkill. But I am sure being a 3/4 ton and Dodge figuring it is used for towing.Let a rear end exploded and your not be going by that stupid 15,000 mile rule and they would try to opt out on coverage. I read the manual closely, because I think 15,000 miles is crazy. Its sort of like the severe service oil changes. Unless you are a mail courier running from the east coast to the west coast only in the fall and the spring. You are in their SEVERE service category.


Don't Ford and GM use the same diff? As I said above, the diff oil change interval is 95,000 miles under Severe Service on an F-250 with a Diesel....
 
Originally Posted By: OVERK1LL


Don't Ford and GM use the same diff? As I said above, the diff oil change interval is 95,000 miles under Severe Service on an F-250 with a Diesel....




GM uses the same 11.50AAM rear and the same 9.25AAM center chunk as the 2500/3500 Dodge. Their recommended intervals are more realistic.

I find it hard to take that Dodge intended for you to change the gear oils as often as you change engine oils...
 
I just checked my service book. I changed all the fluids out at 60K. 77K is just what it has on it now. I didn't start driving the truck until about a year ago. I agree the rear fluid should of been changed before that. It was not my truck at that time though. I still think it is totally ridiculous that Chrysler can make a product where you have to change the gear oil every 15K or even 30K. That is just a poor system that needs to be redesigned with at least a cooler or some other means of making it last. On the plus side I checked my tranny fluid today and it is still just as purple as when I put it in. So i can vouch that after 17,000 miles RP Max Atf is a great product. As long it is approved for use in your vehicle of course. O and as for the $1500, he showed me the slip it was over $1000 in parts. I mean i guess it was not rebuilt exactly. Every part is brand new. He didn't re use anything because it was all scuffed up from the metal flying around in there.
 
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