Transmission Service?

[oldcat1]

I have a 2013 GMC Sierra 2500HD 2WD with 3.73 rear. 32K miles with 20K of that towing a 6K (loaded) TT. I carefully monitor trans temps when towing and it runs in the 145 to 170 degree range almost all the time. I tow at 60 MPH in tow/haul with 6th gear locked out. It has only seen 200 degrees a handful of times (long grade on hot day).

I get free oil changes at the dealer, and they are telling me it's time to have the trans fluid and filter changed. My owners manual says not until 97K (45K with severe duty). I plan on keeping the truck a long time, but this seems like overkill. What do you think?

[Turtle_n_Peeps]

Where do some of you come up with your magic number?

Like 30K? Why not 20K? Or 10K? Hell, why not 1K; after all you can't hurt your vehicle by changing fluids too soon. :R

So the question is; how do you come up with this number?

[retispcsi]

I service transmission at 30K on all my vehs. Tow heavy and drive hard. Cheap insurance. Owned vehs since 1968 and never lost a transmission yet. Just my opinion. Call around for price.

[ib516]

Rip off, money maker, scam, whatever term you prefer. Stick with what the manual says.

PROOF

[DavidP]

ktmrfs wrote:

FWIW, it's interesting that the majority of mfg either don't list, or have a very long interval between brake fluid flush. IMHO a very bad idea. brake fluid absorbs water easily, leads to brake fade and other issues. That's one area where I go with every 2 years and use DOT4+ fluids rather than the commonly recomended DOT3.

Agreed. I flush my fluid annual. I installed Speed Bleeders, makes it real easy. Brake "feel" stays like new. Amazing how brake feel degrades over time with old oxidized fluid. No doubt water retention in the fluid causes a soft pedal.

Service intervals are getting longer and longer. Car manufactures have geared intervals to cost of ownership. The lower they can make the cost of ownership number the more appealing the vehicle is to many prospective buyers. The winners are the MFG’s and those who unload vehicles early. Losers are everyone else.

[colliehauler]

I would change mine earlier if the transmission fluid showed any signs of discoloration or burnt smell as well as moisture contamination.

[gmw_photos]

What's it cost to change the fluid ? $150 or so ? In 200,000 miles, changing it at 30K intervals vs 50K intervals will result in two extra changes. $300 difference over 200K miles is peanuts.

Yes, I'm one of those that changes fluids ahead of schedule. Makes me feel good about my truck !

[ktmrfs]

I believe that your truck uses DexVI which is a synthetic fluid. With the change to DexVI fluid interval changes were extended. As long as you are watching temps and they are ok, I'd go with the severe service change.

And, even if I wasn't in the severe service category, I'd still change it at the severe service interval.

And, for peace of mind, send a sample of the fluid at the severe service off to blackstone labs for analysis. I suspect it will come back that the fluid was in very good shape and you are ok with that service interval.

I've done that on four vehicles with those results, two of which see heavy towing use, and on the same vehicle, the 7500-10K for oil change and in every case the TBN is still high, contamination very low and indications that the change interval is conservative.


FWIW, it's interesting that the majority of mfg either don't list, or have a very long interval between brake fluid flush. IMHO a very bad idea. brake fluid absorbs water easily, leads to brake fade and other issues. That's one area where I go with every 2 years and use DOT4+ fluids rather than the commonly recomended DOT3.

[oldcat1]

Thank you all for your insights. While the manual does not list TT towing as severe duty (they list things such as mining, farming, forest service) I think I will still do the trans service at 45K.

Thanks again, and safe travels

[drsteve]

Changing fluids too often will not damage your truck.

[PDX_Zs]

I have that same trans in our Big Bad Burb.

I can drop the pan, toss in a filter, and refill with seven quarts in half hour. And that is taking my time, petting the dog, and chatting with the bride.

I may squak if the dealer was charging a bunch, but for me it’s easy and cheap enough to do more frequently.

[larry_barnhart]

Because the truck is in our name on the title I feel I am the boss so I changed to synthetic trannie fluid at 12 K miles and have drained the torque converter twice myself. Changed the rear diff 9 times my self and have changed the coolant 2 times and the Allison spin on filter each summer and the brakes have been flushed 3 times plus the steering fluid 3 times. I never disagree how others care for their vehicle's. Also never run the tires to the max mileage or keep the batteries until the truck doesn't start.

chevman

[ppine]

The earlier rule for changing trans fluid was 30k miles, more often for severe conditions. I change mine at 30k and the trans is fine at 175k miles.

[BB_TX]

dodge guy wrote:
...........
It’s amazing to me how people say “what does the owners manual say” when it comes to maint. but when it comes to tow ratings that goes out the window and people say “use 80% of the max”! Well which is it. If the manuf knows best then why not tow the max weight?

Just because the manuf gives a schedule of service does not mean you can’t do it earlier!

My manual shows mileage recommendations for three different levels of usage from normal to severe. The dealer has never asked how I use my truck.

[Me_Again]

Falls right with Quicklube 3500 mile oil changes. That is money maker!

Chris

[DavidP]

I fall in the camp to change it. The whole idea is to change it while it is still bright pink and clean. Wait until the manual suggests or OEM recommendations and it will be oxidized and dirty and at that point any wear and damage is done. This is one of the few times the dealer is right, especially since it is used in “extreme” conditions like towing. When I change fluids in my truck, differentials, transfer case and transmission the fluid coming out looks like the fluid going in. I would change the transmission every 25 K and not wait. Cheap insurance IMO.