With your high mileage, I would use 5w30 with 1 qt trans fluid. Transmission fluid has detergent properties. One quart will slowly remove the gunk. If you have no oil leaks this is a good bet.

 

Do not put tranny fluid in your engine

Hand soap makes things clean but I would not put that in my engine either.

Your manufacturer gave you a manual with the truck. It is the only advice you need.

 

Your manufacturer also wants you to buy new cars. Its baked into their profits.

"The greatest obstacle to discovery is not ignorance -- it is the illusion of knowledge."
Daniel J. Boorstin

 

I switched to Mobil 1 synthetic..and engine runs quieter and at higher pressure

 

Synthetic oil is awesome, however. If you have a vehicle that has not been running synthetic in it since it was reasonably new I'd stick with the O.E. over time your seals in your engine swell with regular oil. it keeps it sealed. sythetic oil does not do that, it is thinner(even though it protects you engine better). It may cause leaks in your gaskets.

I believe that the fluids in your trans/diffs/transfer case are synthetic from the dealer so no worries there.

 

I switched and no problems or leaks, there is also a highmileage Mobil 1 synthetic oil out on the market

 

Did you check for an exhaust manifold leak to see if that was the noise you heard and not the oil

It is super common for this vehicle and has a higher pitched sound and once the engine warms it seals the leak and the noise quiets

 

Considering they asked nearly 7 years ago and have not been back here since I'd assume they figured things out.....

 

I bet your right but if anyone else stumbles across a topic and can learn from it then the post was helpful

 

The ticking sound you hear when the engine is cold on start up is the sound of ticking valves. Because your engine block is aluminum and the exhaust manifold bolts are steel they expand under heat at different rates. You will notice that the clicking sound goes away when its warm. What your problem is, is that some of your exhaust manifold bolts are broken and until the engine warms up there is a slight gap between your manifold and the exhaust from your engine block. As the materials warm up the gap closes and you cant hear the noise due to the metal warming and tightening up.

As far as using a different grade oil you should not listen to tinfoil hat wearing conspiracy theorists spouting about OEM’s trying to build in a car that fails on purpose is crazy. Keep using 5W30, if you want synthetic then use that to feel better about the heat of the desert. I am an engineer and i live in Detroit who works with OEM’s every day. They all want your car to last till its warranty to save them money to not fix it. In that effort they try to make it last as long as it can. Most GM built V8s will get 250,000 miles if serviced and directions followed as stated in the manual.