One more differental topic!

[draymorris]

I use 75-90 and I hual super heavy alot. I thought that the 140 is for heavy load application as well, but for warranty reasons stuck with the 75-90. It would be nice to hear what these different oils do under our conditions. Is 140 really better? Can the 90 get "squeezed" out from between gears allowing metal to touch? Is there anyone out there who has seen a operating temperature difference between the two oils?

 

[RVCrawford]

Just curious but unless you tow in 4 wheel drive why would you use the heavier oil in the front?

 

[jakemeister]

I do tow in 4wheel drive in the winter time... I have a cabin in cloudcroft NM. Its a 9000' MSL and alot of the time Im pulling in 4 wheel drive due to icy and snowy road conditions... then again its usually cold out and im driving slow, so im not sure if it gets hot enough to make a difference.



Has anyone every put 70w-140 synthetic in a jar and seen how "thin" it seems compared to 75w-90? I dont think its much different... its synthetic. . right. . and synthetic seems alot thinner that regular ol' dino lube.



As for heavy load conditions my cab over can weigh up to 5000k and with the weight distrabution and trailer It puts more weight on the front axle. . heavier than normal towing i suspect.

 

[JeffreyHahn]

Why would AAM specify an inappropriate oil for use in their differentials? Is it normal for lubrication engineers to dictate to mechanical engineers which lubricant they need to use for an assembly (from your statement I assume you are a mechanical engineer with a background in lubricating oils)? I am asking out of genuine ignorance, not to be a smarta$$.

I work at AAM in engineering and you would be frightened by what goes on. They are still resting on their laurels because of the contracts with GM.

 

[draymorris]

I work at AAM in engineering and you would be frightened by what goes on. They are still resting on their laurels because of the contracts with GM.

You sure seem to be going out on a limb - you work for AAM engineering!?!?

No offense, but some of us have some questions for you. How many of these axles is AAM hearing about failure on? Are they as good as some have advertised? Do you think they will last 2K - 3k - 4k miles or should i budget in a replacement every 70K or so.



I could go on and on. I am honestly not trying to offend you, just wanting more info on your view.



What oil would you recommend?

 

[JeffreyHahn]

I would venture a guess and say most are good. Any fluid problems, etc, are on DCX. Axles are shipped empty. You've got to remember, this is just a copy of a GM axle. When they bid on DCX they had less than 60 days to come up with 6 axles. They haven't changed since then. There is a serious lack of engineering at AAM. AAM seems to have their head in the sand (or at least, somewhere) when it comes to failures. Nobody I have talked to has heard about failures. No matter what axle mfr. is used, you will still have quality problems. All use 3rd world labor for casting and machining. I have a feeling Dana will be back after '07.

 

[draymorris]

Thanks

Thanks for your honesty. I am in plastic molding and we have agreed to never get into automotive molding because of its competitive nature - they always expect a decrease in price from year to year, yet cost increase year to year - so as a mfr, a company has to do something to decrease cost to stay in business and Quality usually suffers. In the end, the job ends up overseas anyway.



If this problem was so expensive to repair, it would be no big deal.



I hope Cummins does not get pushed too hard by DC and end up making lower quality engines. I wonder where their components come from?

 

[WNowlan]

I work for the lubricant side of the business.



I believe that AAM should consider the heavier fluids for towing in the warmer areas.



One nice thing about the Dodge over the other brands, the truck sits higher off the ground allowing better airflow around the differentials. This helps keep gear box temps down.



When I change mine 9K on 04. 5 3500 4X4 SRW 4:10, I will be going to a 75W-140. I am prepared for any warranty issues. I tow a horse trailer in to the mountains and I am at 13,000 loaded.



It may get slightly less fuel MPG, but I don't care because I bought the truck for the POWER! Let'er BURN :-laf

 

[JeffreyHahn]

The only thing AAM engineering said was the 140 would lower mileage, create a more unbreakable film on parts, but, could increase temperature.