I did front and rear diff and trans at 75k on my 2020

I also did front and rear diff at 2500 after a little break in, paid for the oil change then. I'm sure unnecessary, but old habit

all that other stuff, is just profit for the dealer

[QUOTE]Originally posted by arfmel:
Ask that dealership about their “wallet flush”.[/QUOTE

How true. Last dealer I worked at the service writers were paid commission and spiffs only, no base pay. You can see where this is going…..

One of the writers tried to play that game with me after I had been there about two months. I had a SES light in together with a surge at cruise speeds. Despite a GM extended warranty he tried to tell me that I had to pay for an injection service as the first step.

Told him “Do whatever you want but I’m not paying anything but my deductible.” To his “Well we need to do this first” I said “Shall we go read the Policies and Procedures manual together?”

Well to say that him and I were not the best of “pals” after that is an understatement…..

I had two 4Runners. If you plan on keeping it I would do the service. I did a lot of towing with mine. We do a trip out west every year so I would trailer the bikes, about 3-5k miles of towing 2k and then what was loaded in the truck. I change my brake fluid every 3 years or so. If you using it hard change fluids, if you’re just driving around town hauling kids and soccer balls those can probably wait. I would take a quick look at the service interval for the required intervals (I don’t remember them). I miss my 4Runner!

former service advisor with CarMax, dealing with all makes and models. brother was a tech for 30yrs and I've been a big DIY guy since my teen years. it would be good to do all. really not premature on any unless lifetime fill and if you meet criteria. usually there are normal and extreme driving patterns that dictate what mileage interval is recommended. like towing, daily temps, idle time, traffic or driving threw water. and sometimes it's just time gone by, nothing to do with how many miles. all manufacturers will have different intervals from, mileage to being considered "lifetime fill". had a new 2003 dodge dakota and manufacture rear diff fluid was every 15K and my 2001 Ford Super Duty F250 with 7.3 diesel was considered a "lifetime" fill. you would think the opposite with those vehicles and their most likely owner usage. my sister has a 2006 Scion XA with lifetime fill transmission. it finally has 60K miles and the fluid looks brand new. I've done her OLF and other maintenance for years now and that fluid doesn't change in color, smell or level.

Honda is very big on fluid changes and they last forever like Toyota. our 2011 Pilot bought at 48K miles now has 220K miles and going strong. its 4wd. Honda says the rear differential is every 15K miles. tranny and transfer case is every 30K miles. Honda also has always been an advocate for brake fluid flushes every 3 years no matter the mileage. timing belt every 100K. coolant every 100K. and that's what i do all that at those intervals. i do what honda says and so far so good. plan on making it to 300K before retiring it.

biggest thing is most of these fluid changes are simple DIY if you have time, tools and space. but if you dont then you have to pay for the labor. if still under warranty do at dealer if reasonably priced. otherwise buy the fluids and filters from Toyota or at least buy Toyota fluids wherever you buy from. especially for tranny.

Valpo FZ has good advice.

Trailering is considered severe duty and usually recommends servicing at sooner intervals than average use vehicles.

Also read this, while a GM TSB it many other manufacturers have issued similar TSB’s. For more information look up the actual bulletin using the number at the top of this summary as I’m not able to post the photo of the actual TSB.

GMC GMC TSB 04-06-01-029J

Make:
GMC
Number:
04-06-01-029J
Title:
Unscheduled Supplemental Services (Including Flushing Services and Additives) and Proper use of GM Simplified Maintenance Schedules
Date:
2/28/2020
Models:
2007-2020 Acadia
2006-2009 C Series
2006-2012 Canyon
2015-2020 Canyon
2006-2009 Envoy
2006 Envoy XL
2010 G Van Bus
2006-2020 Savana
2014 Sierra 1500
2019-2020 Sierra 1500
2007-2020 Sierra 2500
2007-2013 Sierra Denali
2015-2019 Sierra Denali
2010-2020 Terrain
2006-2010 Topkick
2006-2010 W Series
2006-2020 Yukon
2006-2013 Yukon Denali
2006-2013 Yukon Denali XL
2006-2020 Yukon XL
Summary:
General Motors takes great pride in offering our dealerships and customers high quality vehicles that require extremely low maintenance over the life of the vehicle. This low cost of ownership builds repeat sales and offers our customers measurable economy of operation against competing vehicles. Our goal is to make the customer experience a key driver of why customers purchase GM products and services. Providing responsible services at the proper intervals supports this goal and will help your dealership earn repeat business. Today, many of your service departments merchandise supplemental services and fluids to customers indicating that these "flushes" have a positive effect on durability of the component part. It should be noted that analyses of returned parts that have been exposed to these aftermarket "flushes" show indications of potential damage and shortened durability. The following information clearly defines the guidelines for servicing GM vehicles.

Thanks all for the valuable info, it is appreciated.