- Joined
- Mar 6, 2022
- Messages
- 8
Good Day,
First post here on BITOG, I recently purchased a used 2008 Silverado QC Z71 LTZ w/ 5.3L, 3.73 gears, and 184K miles. I have been enjoying the truck and have performed an oil change already using Penzoil platinum high milage 5w-30 and a Fram ultra synthetic filter. I would like to change all fluids in the truck, I have looked in the manual and see Trans fluid should be Dexron 4, but for the differentials it listed different viscosities. The trans fluid looks a little brown, I would like to do remove the pan drain, and change the filter then refill, but I have read that this can be detrimental on high milage autos, the 4L60E specifically. Is it a waste of time or would I be asking for trouble by dropping the pan and replacing the filter and refilling? What is the recommended type and weight gear oil recommended for these trucks? Are there any MPG gains to be had in going with amsoil in the differentials?
Edit: I forgot to mention the coolant, this truck has red coolant? The manual says dex cool and it should be good for 150K miles. I'd like to flush it, but I thought dexcool was orange??
Looking forward to your thoughts. Also, I haven't ever had a UOA performed on my vehicles but have a Lexus with 293k miles I would like to do one on.
First post here on BITOG, I recently purchased a used 2008 Silverado QC Z71 LTZ w/ 5.3L, 3.73 gears, and 184K miles. I have been enjoying the truck and have performed an oil change already using Penzoil platinum high milage 5w-30 and a Fram ultra synthetic filter. I would like to change all fluids in the truck, I have looked in the manual and see Trans fluid should be Dexron 4, but for the differentials it listed different viscosities. The trans fluid looks a little brown, I would like to do remove the pan drain, and change the filter then refill, but I have read that this can be detrimental on high milage autos, the 4L60E specifically. Is it a waste of time or would I be asking for trouble by dropping the pan and replacing the filter and refilling? What is the recommended type and weight gear oil recommended for these trucks? Are there any MPG gains to be had in going with amsoil in the differentials?
Edit: I forgot to mention the coolant, this truck has red coolant? The manual says dex cool and it should be good for 150K miles. I'd like to flush it, but I thought dexcool was orange??
Looking forward to your thoughts. Also, I haven't ever had a UOA performed on my vehicles but have a Lexus with 293k miles I would like to do one on.
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