First fluid changes on the new K2's??

[LongrangeLauber]

Just picked up a High Country on Saturday and is absolutely awesome so far. Have about 330 miles as it sits right now, climbing every day. I was just wondering when yall did the first fluid changes on various components of the truck. I know on my other truck when I got new gears installed, I replaced the diff fluids after 500 miles to get out any break in shavings. When I installed a new transmission, the builder recommended to do it after the first 2k miles and I also changed the trans filter at that time as well. Wondering when I should do the following fluids:

 

• Oil
• Transmission Fluid
• Transfer Case Fluid
• Differential Fluids

I plan on keeping this truck a long time and want to do everything I can to help extend the life of the components. I aint a stranger to anything under the hood of a vehicle, so I will be performing all these myself, unless a transmission flush is recommended as well as a new filter. Thanks y'all

[gmtech4]

Owners manual is your friend buddy !! Lol

[beetle]

Your going to get a lot of opinions on this, some will say just let the engine oil go until xxxx thousand miles others will do it with-in the first 1000 miles. I did the first oil change myself at 700 miles, you should have seen how nasty and dirty it was with a ton of fine metallic particles. As far as the rest of your drivetrain, I wouldn't bother.

[LongrangeLauber]

Owners manual is your friend buddy !! Lol

Read that thing front to back and it doesn't say anything about break in stuff I'm just going off my past experience. I'll probably do the diffs at 1000 miles as well as an oil change. I'll give my dealership a call and ask the service writer what is recommended.

 

You gotta remember, it's GM, they expect you to know stuff that's not written down lol

 

Sent while in 'Murica...

[2017SierraSLT]

The differential oil in my '13 with 10k miles was nasty. I would change that out with a high end synthetic such as Amsoil Severe Gear 75W90. I would get the factory fill engine oil out by 1k miles, and change again at 5k intervals using a high end top tier synthetic, such as Amsoil or Pennzoil Ultra.

[LongrangeLauber]

The differential oil in my '13 with 10k miles was nasty. I would change that out with a high end synthetic such as Amsoil Severe Gear 75W90. I would get the factory fill oil out by 1k miles, and change again at 5k intervals using a high end top tier synthetic, such as Amsoil or Pennzoil Ultra.

I agree with the 1k factory fill replacement. Every 5k is wayyyy overkill though. My other truck was every 30k, I'll have to check on this one but I feel like it's around 50k or more

 

Sent while in 'Murica...

[2017SierraSLT]

I was referring to the engine oil....

[LongrangeLauber]

Oh wow, that went completely over my head. Should have realized when you said Pennzoil lol.

 

But for my diffs and engine I use mobile 1 synthetics. Extended Performance for the engine oil, and full syn for the rear diffs

 

Sent while in 'Murica...

[redwngr]

The differential oil in my '13 with 10k miles was nasty. I would change that out with a high end synthetic such as Amsoil Severe Gear 75W90. I would get the factory fill engine oil out by 1k miles, and change again at 5k intervals using a high end top tier synthetic, such as Amsoil or Pennzoil Ultra.

Gear oils smell nasty even when they are new.

 

Factory rear diff oil is synthetic SAE 75W-85 (front is conventional SAE 80W-90 ). There is NO recommended change interval for the differentials (so called fill-for-life).

[bigsapper]

 

Your going to get a lot of opinions on this, some will say just let the engine oil go until xxxx thousand miles others will do it with-in the first 1000 miles. I did the first oil change myself at 700 miles, you should have seen how nasty and dirty it was with a ton of fine metallic particles. As far as the rest of your drivetrain, I wouldn't bother.

lol. How can you state that for the engine then just dismiss out of hand the rest of the drivetrain?

 

You have a 100k mile warranty on the drivetrain following GM's recommended service intervals. (hint, hint)

 

If you have a specific high demand scenario, it probably impacts all components of the drivetrain. Plan accordingly.

[LongrangeLauber]

Gear oils smell nasty even when they are new.

 

Factory rear diff oil is synthetic SAE 75W-85 (front is conventional SAE 80W-90 ). There is NO recommended change interval for the differentials (so called fill-for-life).

He could have been referring to the fluid actually having some metal shavings and the magnets built up with crap

 

Sent while in 'Murica...

[2017SierraSLT]

There was a fair amount of shavings on the magnets, but that gear oil was not only low, but black and nasty. The Amsoil was nothing of the sort. The 75W85 viscosity must be a change for '14-'15. The recommended viscosity for my '13 was 75W90.

[KARNUT]

I would go by the owners manual, when I was out of warranty I switch the oil to synthetic and go max miles on it or one year. The last few trucks had synthetic in the transmission went 100k on it. Same with the diffs. Never a failure.

[LongrangeLauber]

I would go by the owners manual, when I was out of warranty I switch the oil to synthetic and go max miles on it or one year. The last few trucks had synthetic in the transmission went 100k on it. Same with the diffs. Never a failure.

Rear calls for syn I have plenty of 80w90 dino oil for the front diff. And yeah that's what's recommended on the trans is 100k

 

Sent while in 'Murica...

[LongrangeLauber]

There was a fair amount of shavings on the magnets, but that gear oil was not only low, but black and nasty. The Amsoil was nothing of the sort. The 75W85 viscosity must be a change for '14-'15. The recommended viscosity for my '13 was 75W90.

I'm just going to stick to 75w90 Mobil 1 full syn. Ain't no way there's a huge difference between that and the recommended 75w85. I've thought about checking the factory fill level but I haven't heard any odd noises and it's only gonna be in there 1k miles so it should be fine

 

Sent while in 'Murica...