2006 Gmc 2500hd 6.0l, Switch Over All Fluids To Synthetic?

hotbread597 · June 2, 2008

I have a GMC Sierra 2500HD 6.0L 4X4, I love the truck, I have a 30000miles on it, and i Haul quite a bit with it. I switched the truck over to the amsoil synthetic engine oil and im quite happy with it. I was wondering if there is any advantage or disadvantage to swtiching over my tramission trasnfercase and differentials to an amsoil or some other synthetic oil? where i live its get to -40F alot throughout the winter so im not sure if the synthetic oil would be better in the winter as well. I was told that swtiching to synthetic in the transmission could cause it to slip when shifting? Just wondering what everyone else thinks thanks... Brad

BigJayDogg3 · June 2, 2008

I'm not sure of it myself, but synthetic oil is something that is commonly discussed on here. Try searching.

Woodcutter · June 2, 2008

I personally wouldn't spend the money to switch over to all sythetics, but you may actually gain some protection in those extreme temperatures by doing it. I think the rear differential fluid is fully synthetic from the factory.

95Sierra2500 · June 2, 2008

Check your owner's manual/with a dealer to see which parts already have synthetic in them. The rest I'd consider switching, especially if you're at all concerned about gas mileage and/or longevity.

As for synthetic in the trans, I've got two vehicles that I switched to synthetic in the trans and have had 0 issues. Think about it, it's got to hold up to the same standards as regular tranny oil, why would it make your trans slip? It just holds up better under temperatures.

jpringle3 · June 7, 2008

I would recommend changing the diff oils to synthetic, I did mine at 12,000, I am looking into getting the transmission flushed out and switched to synthetic. Now that I can get the Manuals for this thing I may wait and see what they say about doing it, and do it my self. Anybody that tells you that synthetic harms anything is "Full of it" as long as the oil is spec'd right it will preform better, in my opinion it flows better in cold weather, and handles high heat better without breaking down. The motor oil part, for you should be a definite benefit, I live in Rock Creek and we don't get that much real cold weather, and needing CJ oil I bought a pail of Shell Rotella and will be changing the oil the second time at 15,000 k witch will be real soon. I will see the price and availability of synthetic oils in the fall. One thing I did do is drill the oil drain plug and install a pencil magnet in it, that is a personal preference for me on my GM gas unit's I have oil pan plugs from the old 8.2 diesels. PLAY SAFE!

BlackSilver · June 7, 2008

Generally I think synthetics are a waste of money, but in your cold climate I think they'd be worth the money. Can't imagine why it would cause transmission slippage.

Go for it.

The Factory Man · June 9, 2008

Generally I think synthetics are a waste of money, but in your cold climate I think they'd be worth the money. Can't imagine why it would cause transmission slippage. Go for it.

Engine dyno tests show a horsepower and torque increase after switching to synthetic. How is this possible? Synthetic reduces friction and anytime you can reduce friction, that is a good thing. That friction is what wears your parts out. Increase fuel efficiency and reduce wear, now that sounds like a winner to me. Now do you still think synthetics are a waste of money?

BigJayDogg3 · June 9, 2008

Generally I think synthetics are a waste of money, but in your cold climate I think they'd be worth the money. Can't imagine why it would cause transmission slippage. Go for it.

Engine dyno tests show a horsepower and torque increase after switching to synthetic. How is this possible? Synthetic reduces friction and anytime you can reduce friction, that is a good thing. That friction is what wears your parts out. Increase fuel efficiency and reduce wear, now that sounds like a winner to me. Now do you still think synthetics are a waste of money?

I do because everyone that I talked to about synthetics, be it a shade tree mechanic or someone that has been certified, they told me that unless you are doing extended drain intervals, it isn't worth the extra money. Me, in all my paranoia, decided I'd much rather change my oil out "too much" than not enough, so I change my oil between 3000-4000 miles, so synthetic oil wouldn't do anything for me but drain my pocket faster.