2016 90K maintenance round-up

[CamGTP]

Gear oil is only clear/golden for a limited amount of time, it changes to a brown/black color rather quickly. An oil analysis would be best to know when it should be changed.

 

To me it's every 50-80k miles for most fluids. Coolant can go much longer, 100-150k miles easy.

[steelerdude15]

4 minutes ago, CamGTP said:

Gear oil is only clear/golden for a limited amount of time, it changes to a brown/black color rather quickly. An oil analysis would be best to know when it should be changed.

 

To me it's every 50-80k miles for most fluids. Coolant can go much longer, 100-150k miles easy.

Thanks for the info. I know coolant can last as long as you said and I know once Dexcool coolant starts to gum it, it needs replaced.

Edited October 25, 2021 by steelerdude15

[NWI Denali]

9 hours ago, dp454so said:

What intervals do you recommend for an 8L90 with 108k on the odo? 

Do you know if it's ever been changed? I would do a pan drop and put the new and revised mobil1 atf in and new filter. Then I'd do it probably every 50k from there on out 

[NWI Denali]

9 hours ago, dp454so said:

What intervals do you recommend for an 8L90 with 108k on the odo? 

Do you know if it's ever been changed? I would do a pan drop and put the new and revised mobil1 atf in and new filter. Then I'd do it probably every 50k from there on out 

[NWI Denali]

9 hours ago, dp454so said:

What intervals do you recommend for an 8L90 with 108k on the odo? 

Do you know if it's ever been changed? I would do a pan drop and put the new and revised mobil1 atf in and new filter. Then I'd do it probably every 50k from there on out 

[NWI Denali]

9 hours ago, dp454so said:

What intervals do you recommend for an 8L90 with 108k on the odo? 

Do you know if it's ever been changed? I would do a pan drop and put the new and revised mobil1 atf in and new filter. Then I'd do it probably every 50k from there on out 

[ftwhite]

Couple comments (opinions):

 

GM calls for Transmission fluid every 45k for severe usage, but defines severe usage as "hilly" or "city stop and go" driving, which to me seems very common. This tells me the factory transmission fluid can wear out much sooner than the 100+k many people say they are extending theirs to. So every 30k-45k seems like a good investment to me, especially if you do it yourself where fluid cost is the only cost. I changed mine at 60k, and moved off the Mobile1/GM because my 8speed transmission has been very poorly behaved (shudders, hard shifts when cold, over heating). Better quality fluid seems to really help. My experience. 

 

Transfer Case is always being used. These trucks don't have hubs that unlock, and the transfer case doesn't stop spinning the internals even in 2w drive. If this hasn't been done on your truck yet, you'll be surprised at how much metal shavings come out on the drain magnet when you change the fluid. I'd also change this fluid 30-45k.

 

I think there are two approaches to fluid changes: try to get every bit of usage out of the fluid you can to save money on fluids; or change fluids as often as you can afford to get every bit of usage out of the truck that you can. I haven't met anyone on this forum yet who can prove one approach is better than the other, so just pick the one you like better and ignore the advice to the contrary. Their just opinions.
 

[Grumpy Bear]

3 minutes ago, ftwhite said:

I think there are two approaches to fluid changes: try to get every bit of usage out of the fluid you can to save money on fluids; or change fluids as often as you can afford to get every bit of usage out of the truck that you can. I haven't met anyone on this forum yet who can prove one approach is better than the other

 

https://www.gmperformancemotor.com/category/GENG.html?CatListingOffset=12&Offset=12&Per_Page=12&Sort_By=disp_order

 

Reman trans $3,100 plus install. Yikes! How expensive are the fluids you are buying? 

 

I use Red Line D6 at $13 a quart. Just the transmission cost covers 238 quarts or 40 drop and fills. If done on 40K OCI's that's 1.6 MILLION MILES before fluid cost = transmission cost. And I'm pretty sure you can double the life of the transmission with 40K fluid changes. Been there, done that. 

 

Now that wasn't hard, eh? Didn't even have to produce a transmission that has. Just the math alone tells the story. 

[Black02Silverado]

23 hours ago, dp454so said:

Question to you fellas:

 

If the truck is now at 108k miles, and I've serviced the trans per GM recommendations to date (more or less), and I want to keep the truck, how often - going forward - should I change the trans fluid and filter?

 

every 20k / 30k?

 

FWIW - I'm planning to start using the AMSOIL trans fluid.

I do  mine every 45 to 50k using AMSOIL.  I did go a bit longer once on my 2002 Silverado to 100k.  I had the fluid analyzed and it came back good and the wear metals all came back still good.  But I still believe in changing early.  All in all I just got lazy with it.

 

The differentials I go 100k.  When I sent that fluid off the lab recommending going to 120k next time.  This is even with towing a 5klbs trailer on once a month or so.

[Black02Silverado]

23 hours ago, dp454so said:

Question to you fellas:

 

If the truck is now at 108k miles, and I've serviced the trans per GM recommendations to date (more or less), and I want to keep the truck, how often - going forward - should I change the trans fluid and filter?

 

every 20k / 30k?

 

FWIW - I'm planning to start using the AMSOIL trans fluid.

double post, sorry

Edited October 25, 2021 by Black02Silverado

[customboss]

On 10/23/2021 at 9:04 PM, MikeBMW said:

I dunno. I already know many here hate the damn dealer, but I've had great service with mine.
Took it in for the transmission fluid change and asked if they just do a drain and refill - I was told they do a total flush and replacement of fluids.
Also, my warranty has free oil changes (for the oil, it seems, not the labor) and, my last service with the transmission also included tire rotation, fluid top-offs for brake fluid - wasn't needed - and washer fluid as well as coolant - also, not needed.
They mentioned next time I bring it in, in January, they'll do the differential fluids as well as another oil service.
I've had them install all of my cameras - front, bed cam. tow mirror cams (and the tow mirrors), also, the new black wheels (from Chevy) for my 35s wherein the service tech noticed a small scratch on one of the wheels and fixed it for free.
I've bought nearly all of my add-ons from the Chevy website and I get a great product and someone to blame if it isn't.
The only exceptions are the lift, Billsteins, lockbox under the center front seat storage and headlights.
I like my dealer, sorry too many don't.
 

A good dealer that treats you fair and is competent is money in the bank. Even if you DIY on most things. 

[steelerdude15]

8 hours ago, ftwhite said:

Couple comments (opinions):

 

GM calls for Transmission fluid every 45k for severe usage, but defines severe usage as "hilly" or "city stop and go" driving, which to me seems very common. This tells me the factory transmission fluid can wear out much sooner than the 100+k many people say they are extending theirs to. So every 30k-45k seems like a good investment to me, especially if you do it yourself where fluid cost is the only cost. I changed mine at 60k, and moved off the Mobile1/GM because my 8speed transmission has been very poorly behaved (shudders, hard shifts when cold, over heating). Better quality fluid seems to really help. My experience. 

 

Transfer Case is always being used. These trucks don't have hubs that unlock, and the transfer case doesn't stop spinning the internals even in 2w drive. If this hasn't been done on your truck yet, you'll be surprised at how much metal shavings come out on the drain magnet when you change the fluid. I'd also change this fluid 30-45k.

 

I think there are two approaches to fluid changes: try to get every bit of usage out of the fluid you can to save money on fluids; or change fluids as often as you can afford to get every bit of usage out of the truck that you can. I haven't met anyone on this forum yet who can prove one approach is better than the other, so just pick the one you like better and ignore the advice to the contrary. Their just opinions.
 

Great post.

[Grumpy Bear]

On 10/23/2021 at 2:03 PM, dp454so said:

Hey fellas, 

 

my current rig ('16 ltz 6.2, etc) Looking at the lineup of the many multiple boxes to check for a 90k+ service interval and need some input regarding some of the recommended changes.  The truck is at 108K but is a DD and not used for towing much, and I try to stay out of the fun pedal.  oil changed per system recommendations using Mobile1.

 

GM recommends: (i'm only showing what I need to do here)

- rotate tires.  I'll do that.

- air cleaner.  I'll do that. 

- spark plugs - Need help here.  What type of plugs have you tried and what works well with this engine?  

- tans fluid - I'll do this.  will be replacing myself due to the great content on this forum

- transfer case - I'll do this.  need to change but delaying because xfer case isnt used regularly. any best practices and experiences  recommended. 

- drain and fill engine cooling system - I'll do this.   truck was built in '16, it's '21, time for a flush and refill.  Don't expect much drama here and think I know what I'm doing.

- brake fluid - I'll do this.  I have never changed the brake fluid but will be upgrading the stockers to the Powerstop Z36 kit.  These stock brakes never performed like I wanted but I don't see the value in spending the high $$$ on the brembo kit for a truck with 108K on the OD.  If you'all have recommendations on this sutiation, i'd happily consider. 

- fuel filter - for the life of me, I can't find a guide on how to do this.  Any insight is appreciated. I'd like to do this on my own.

 

Cheers.

 

Oil change: Only thing I'm going to say here is change the VLOM filter. 

 

Tires: As I buy my tires from the shop I get free rotations and do so every 5K miles. Balance cost and I do that every 10K. Once a year I have the alignment adjusted. I am ****** about tire pressures.  I'm a pretty moderate driver and this 5 point routine has blessed me with 125K mile or six year service when using A/S type tires. Just say'n 

 

Air Cleaner: OEM Direct Fit (blue wrapper) is a very good (efficient) filter. 

 

Plugs: Stay with the OEM heat range and type. If you just have to have a name brand...NGK...they are the OEM supplier.  Wires is a good idea at this point too. 

 

Trans fluid: Hope this isn't the first service. There is no such thing as 'normal service'. Use the severe schedule. 

 

Transfer case / Diffs: Change them anyway

 

Cooling system: Yep. Ya know...if you drop (siphon) the overflow tank and fill it twice a season you never have to do this service. Glycol doesn't wear out. Additives deplete. Depletion is the reason you change it.  

 

Brake fluid. Best done with a power bleeder and a good amount of fluid to each wheel. Here's an AMSOIL 3/4 commercial plug. One of the highest boiling points wet or dry in the business. Personally I'm a stock brakes guy. Pad and rotors. Opinions vary. My experience does not. Currently at 150K on the system that it came with and 50%+ pad/rotor left to do. Stops nice too. 

 

Fuel filter is in the tank and part of the pump assembly. No service.  

 

For what value you find it this.... 

[ftwhite]

More thoughts -

change your cabin filter. I was amazed how dirty this could get just from one long road trip. Find a cheap source online, stock up on a few. I change mine 3-4times a year and don't feel its too much. Always find dirt and other junk in it. 

 

Check the age of the battery. I hate cheap batteries, so I always replace mine (with Northstar), and then every 5y. I guess with good jump packs now this is maybe overkill, but I'm that way.  

 

Because I like weekend truck projects, and been on the wrong side of failures:

I don't know how long I'll go on my front hubs. My Jeep's seem to go through them around 100-120k (timkin I think). Not sure what causes GMs to wear out yet, but having had one fail on a road trip (not a quick fix with tools in the truck), I am of the persuasion for this to be preventative rather than reactive. 

 

Similar for ball Joints and steering end links. I don't really trust them past 100k, but I am not there yet (61k), but I will replace when I get there. Probably together with hubs.  

 

U-joints: I don't get how these things wear. When I replaced them on my Jeep TJ just as a high mileage project (110k), looking inside the caps, it didn't make sense how they didn't blow up. It was rusty, gritty and black inside where the needle bearing were. To me, it seemed like they should have already failed. However, I have never had one fail. Magic I guess . This is a pain to do, even with a good press. But fun none the less. 

Take the belt off and check the pulleys. Especially the water pump. Mine was close to failing, but I caught it (wobbly). Listen for any rattles, squeaks, or roughness. Water pump is easy, alternator too, but more expensive. Idler and tensioner are simple too and pretty inexpensive. Never done the AC, on any car, truck or jeep.  

I like 100k because its when you get to do the big items and trade factory stuff for higher quality parts. Again, that just how I see it. The other side of the coin is: if the factory got you this far, whey not use the same stuff? Because, I don't. Except brake rotors. GM factory rotors are indestructible. Having tried Centric, EBC, and Napa on other trucks and SUVs...I really like the GM factory.   

   

[Black02Silverado]

Speaking of cabin filters.  I got a K&N.  Super easy to just take it out, clean it and put it back in.