1) Does anyone have experience with the Valvoline 5W-40 Synthetic?How about the Amsoil Series 3000 5W-30 Synthetic?
2) Does anyone know if the front and rear axles and NV5600 tranny come with synthetic fluids from the factory? Any point in going to the Amsoil synthetics for the axles and tranny? I tow a 7,000 lb trailer.
3) Anyone have experience withthe Banks 5 inch monster exhaust system?

 

AMSoil is some good stuff. . .I have it running throughout my rig. just by changeing the fluids in the diff's tranny, and engine over to synthetics I gained nearly 1mpg. . .I'm sold

anyway, the NV5600 and the axels on these trucks come from tha factory with synthetics already in. however changeing them out every so often is not a bad idea. the 5w30 amsoil makes is designed just for the NV5600 and other new venture products that use that weight of oil. I noticed better shifting and less noise from my tranny not long after putting the stuff in.

since you are only towing 7000 pounds, I would stick with the 75-90 SVG oil for the differentials. when you go above 12-14,000 is when I would say the 75-140 would be needed.

hope this helps.

 

Thanks,
Which grade of Amsoil do you recommend for the CTD? The 15W-40 or theSeries 3000 5W-30?
Also, do you need to add a friction modifier to the rear axle? Any views on the Banks monster exhaust?

 

the oil is rather climate dependent. in the more northern reaches of the states I would use a lighter weight oil so it remains more fluid at the colder temps, then in the summer use a heavier oil. here in the south where I am 15w40 can be used year round.

friction modifier does not need to be added to 03 and later trucks. however 02 and earlier does need it. the new AAM axels use worm gears instead of clutches for the Limited slip function.

the exhaust. . .well, you already have a full 4 inch exhaust stock on 04.5's and later. you wont gain anything there. your best bet would be to replace the muffler if you looking at something a bit less restrictive.

 

You can use 15w40 year round if you live where it never gets lower then around 10 degrees above zero. The 5w30 is also good for year round use for the people who live where it gets down to -40 below zero. My self I will be trying out the 5w30 HDD on my next oil change.