Engine/Transmission (1998.5 - 2002) Any benefit to synthetic in the front diff..

[klenger]

... if I hardly ever use 4WD? I'm getting ready to change all the fluids in my truck as I'm comming up on 30,000 miles. I use Amsoil (no flaming) Series 2000 74W-140 in the back end, and am wondering if there would be any benefit to putting Amsoil 75W-90 in the front diff. or just go with conventional gear lube. I'm really not concerned about wear as I hardly ever use 4WD anyway, but would synthetic in the front help mileage while in 2WD?

 

[fredflinstone]

I would say that you should strongly consider running synthetic in your front diff if you consider the fact that the spider gears are allways turning. When you think about how fast those little gears are turning when you driving at 75 mph it rather astounding. I personally went ahead and added the Amsoil 75-90 in mine figuring that I will have the truck for many years and it's cheaper and easier to put a good lube in now than to spend a coupel hours and a 100 bucks replacing the spiders in a couple years. But I also plan on having my truck till it falls apart and put alot of miles on where if you don't really plan on keeping your truck longer than a few years you may be money ahead to just leave dino in the front? Just my two cents Seth

 

[jerrethomas]

the spider gears only rotate when you are making a turn that would require differential action. when you are going straight, the whole carrier inside rotates as one. OR, if you get stuck and spin it will prolly spin one wheel in the back which will cause it to create differantial action also. some one will correct me if i'm wrong but i think the front might be a posi. i know in mine when you try to make a turn in the hardpack dirt it bucks and carries on like the front worn't slip, making me think it's a posi.

 

[illflem]

I use Chevron Delo Gear Lubricant ESI SAE 80W-90 in the differentials, best of both worlds, rated right up there with synthetics, easy availability everywhere and the best part - I pay $28 for a 5 gallon tub. It's also availible in 75W-140. Chevron Delo ESI were the first nonsynthetic gear oils approved for the 750,000-mile extended warranty program in Dana/Spicer axles.

http://library.cbest.chevron.com/lu...fbf9ee13d6fb12c788256628007d0d4d?OpenDocument

 

[TomGolden]

I switched my diff lube (both front & rear) to Amsoil series 2000 75W-90 at around 35K miles. I can't say with 100% certainty, but I would bet a cold Guinness that in my truck at least, both diffs had dino lube from the factory, not synthetics.



Anyway, Ken, I only run in 4x4 mode maybe a dozen times a year, almost exclusively on hunting trips, so I'm in the same boat as you are it seems. I decided to go synthetics everywhere (6 speed and Xfer case too) for a couple reasons. It makes me feel a little better, and now I get all my lubes from one place, and with both diffs running the same thing, I don't have to remember one more thing



Tom

 

[klenger]

Here's what I'm thinking of doing for the 30K fluid changes:



Front Axle - Amsoil 80W90 AGL-QT



Rear Axle - Amsoil Series 2000 75W-140 TGO-QT



NV5600 Transmission - Quaker State Synchromesh Fluid MS-9224



Transfer Case - Amsoil ATF-QT



As far as I can tell, all these products meet the specifications from Dodge. I want to be conservative, and not substitute a product because it is sort of like the correct stuff (no flaming please, it's just how I feel). That's why I'm planning on the Quaker State MS-9224 for the NV5600. On the other hand, I don't requre that a product be "API Certified", so let's not go there either. I just want to make sure that I'm understanding the specs correctly.



BTW, the reason for 80W-90 in the front and 75W-140 in the rear is bacause I tow heavy. It would be nice to use the same in both, but it doesn't make sense for my application.



Truck is 2001. 5 2500 QC, 4WD, NV-5600, 4. 10, LSD, Mag-Hytec in rear towing 10,000 lb 5er.



Thanks for any and all feedback (even if I don't agree)



I would like to contine this thread here.