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What should I service?

Clancaster23

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So, I have a '21 Gladiator that I've had since a little over 15,000 miles. I'm a bit over 51,000 miles and I'll probably have it for another 20,000 or so before I can swap it out. I'm not used to having a vehicle with this many miles on it as I usually trade it in well beforehand. Since I will be keeping it for a while longer, I want to try to keep it in as good a shape as I can so I'm going to have to do some upkeep on it. Looking to see what I need to change/check with this number of miles on it. I have already swapped out all the shocks with Bilsteins so got that covered. Put brakes all around about 6 months ago so that's good for a while. I don't do a lot of off roading and have yet to tow something heavy with it so haven't been really hard on it. Basically, just daily driving. and it runs and shifts like it should, but I do run 35s on it. Looking at potentially the differential fluids, not sure what else. Plugs? Transmission fluid?
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Bandit’s Lair

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Mostly follow what is in the service manual. Basic stuff. Oil changes, tire rotations, see to your greasable points with that. Good idea to do differential fluid every now and again to check status and if you ever get into deep water. These aren’t especially hard to do work on so it’s a better vehicle than some to keep long term.
 

Remy_Dog

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Good idea to change your transmission fluid and filter as well. Jeep claims it’s good for a ā€œlifetimeā€ but ZF, the manufacturer of the transmission recommends changing the fluid around 50,000 miles or so. I’m at 57,000 miles and I’m changing the fluids in the diffs, transfer case , transmission fluid and filter.
 

Maximus Gladius

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So, I have a '21 Gladiator that I've had since a little over 15,000 miles. I'm a bit over 51,000 miles and I'll probably have it for another 20,000 or so before I can swap it out. I'm not used to having a vehicle with this many miles on it as I usually trade it in well beforehand. Since I will be keeping it for a while longer, I want to try to keep it in as good a shape as I can so I'm going to have to do some upkeep on it. Looking to see what I need to change/check with this number of miles on it. I have already swapped out all the shocks with Bilsteins so got that covered. Put brakes all around about 6 months ago so that's good for a while. I don't do a lot of off roading and have yet to tow something heavy with it so haven't been really hard on it. Basically, just daily driving. and it runs and shifts like it should, but I do run 35s on it. Looking at potentially the differential fluids, not sure what else. Plugs? Transmission fluid?
I’m assuming you still have warranty?? I’d stick to what your book is recommending just as @Bandit’s Lair has said. If you’re going ahead with suggestions, what’s your wrenching skill level? Would you do this service yourself or have the dealership do it? You looking to save money, doing just the basic stuff or go all out?

In all these miles, have you serviced the diffs, transfer case, or transmission and are you trading in before warranty time lines are up? If trading in is your goal, doing these services may help in the valuation of the trade.

If it were me, (consider this for your next ā€œnew oneā€) by the time I hit 50-60k miles, I would have changed all the fluids within the first 1000 miles and perform annual oil changes thereafter, …on everything.
 

Luisftorresc

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Change the fluids on Differentials, transfer case, transmission if you can, flush the cooling system and add new coolant (very important nobody talks about this one).
That's it since you do only road miles it doesn't need much.
 

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Bandit’s Lair

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Change the fluids on Differentials, transfer case, transmission if you can, flush the cooling system and add new coolant (very important nobody talks about this one).
That's it since you do only road miles it doesn't need much.
I hate doing coolant. I’ve done it but there’s a 50/50 chance the water pump goes right after you do it. I’ve had that happen a few times.
 
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Clancaster23

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Not sure I'm still under any factory warranty. Mine is a '21 so I may be past the 5-year mark. Not quite at the 60k miles mark. I did have to take it in back in October to get some corrosion work done on it. The hood edge and one hinge was rusting under the paint and I believe I barely made the 5-year window on that.

I'd be doing all of this myself. I have never done any cooling or transmission work, so I'd be learning but I'm willing. I have changed rear end fluid before on a Mustang that I have to swap out the rear axle on, so I have a little familiarity with that so I do have some mechanical ability. Just looking to do the basics to keep it running well until it's trade in time.
 

Remy_Dog

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@Clancaster23 Your warranty won’t cover routine fluid changes, so I wouldn’t waste time on that. The items I noted in my earlier reply are changes you can do yourself if even somewhat mechanically inclined. If you search the forum you’ll find that @ShadowsPapa is legit and has soundly advised on these topics. Since your trading soon and you indicate no issues I wouldn’t overthink this.
 
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Remy_Dog

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I hate doing coolant. I’ve done it but there’s a 50/50 chance the water pump goes right after you do it. I’ve had that happen a few times.
Agreed, coolant is a different animal and not something to be taken lightly.
 

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Maximus Gladius

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g2020

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See the maintenance list at the beginning of my post on Key Info. The first attachment at the end of the same post is the same list plus capacities and service intervals.

In all cases, make sure that the product meets manufacturer specs.

  1. Replacing spark plugs is a 100K item, but some folks recommend earlier especially for severe use such as off-road and/or towing
  2. A pan drop, or (automatic) transmission drain & fill, can wait until 93,000 miles for a stock daily driver vehicle, but many on this site recommend earlier because the ATF in the transmission is absolutely not a lifetime fluid and doing a drain & fill (greatly) improves shifting; never do a transmission flush
  3. Transfer case: Change the ATF+4 in the transfer case; this job is easy; Valvoline ATF+4 is every bit as good as MOPAR
  4. Before doing a coolant flush or just a radiator drain & fill, consider replacing the thermostat and water pump if your vehicle is up there in miles (your vehicle isn't)
  5. Rear differential: If you have Trac-Lok / limited-slip rear differential, make sure that the gear oil contains friction modifier; friction modifier is not required for the front differential, but it won't hurt the front diff either
  6. Engine air filter: Change it if you haven't; this is easy and a no-brainer
  7. Buy cabin air filters in bulk online (at least two or three); the prices at auto parts stores are stupid high
It's good that you've already taken care of the brakes (and brake fluid, of course). Another possible maintenance item is monthly replacement of the correct MOPAR PSF in the power steering fluid reservoir. I do this using a turkey baster. Learned how to do this by reading a post by @Hootbro. Even after just one reservoir-only PSF replacement, steering improves.

For others who read this, we should always keep in mind Motor Oil & Oil Filter Service Intervals.

Enjoy your Gladiator.
 
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Dilly’S Willy

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I’m assuming you still have warranty?? I’d stick to what your book is recommending just as @Bandit’s Lair has said. If you’re going ahead with suggestions, what’s your wrenching skill level? Would you do this service yourself or have the dealership do it? You looking to save money, doing just the basic stuff or go all out?

In all these miles, have you serviced the diffs, transfer case, or transmission and are you trading in before warranty time lines are up? If trading in is your goal, doing these services may help in the valuation of the trade.

If it were me, (consider this for your next ā€œnew oneā€) by the time I hit 50-60k miles, I would have changed all the fluids within the first 1000 miles and perform annual oil changes thereafter, …on everything.
The dealers near me quoted almost $2500 for the manual transmission, diffs, and t-case fluids. I promptly said NO THANK YOU. I can do that myself.

I hate doing coolant. I’ve done it but there’s a 50/50 chance the water pump goes right after you do it. I’ve had that happen a few times.
When are the water pumps recommended to be replaced on the JT? I'm assuming about 100k miles? When I do the timing belt/tensioner on my Subaru I always replace the water pump at the same time, since it's driven off the belt.

Not sure I'm still under any factory warranty. Mine is a '21 so I may be past the 5-year mark. Not quite at the 60k miles mark. I did have to take it in back in October to get some corrosion work done on it. The hood edge and one hinge was rusting under the paint and I believe I barely made the 5-year window on that.

I'd be doing all of this myself. I have never done any cooling or transmission work, so I'd be learning but I'm willing. I have changed rear end fluid before on a Mustang that I have to swap out the rear axle on, so I have a little familiarity with that so I do have some mechanical ability. Just looking to do the basics to keep it running well until it's trade in time.
You may still have factory powertrain even thought it's a 2021. My Willys is a 2021 but it was sold between April/May that year, so that's when the powertrain warranty ends for me. You COULD extend it if you wanted, but it WILL cost you.

The warranty follows that date of sale, not the date of manufacture or beginning of that calendar year.

Whoah. Trading in a vehicle because it has 70k miles on it is basically like burning money because it wasn’t perfectly crisp anymore. šŸ˜…
IKR?! Just lease the damn thing at that point. Mine was a lease the previous owner bought out to trade on a 4Runner at the dealer I bought it from.

Side note:
IDK why but Toyota drivers these days either drive like old men or road rage. A couple days ago a Nissan Juke passed a 5th Tacoma in a passing zone...well the Tacoma driver didn't like that and attempted to PIT the guy! I was in a work van behind them, wish I caught it on camera.
 

Sandman 4x4

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Whoah. Trading in a vehicle because it has 70k miles on it is basically like burning money because it wasn’t perfectly crisp anymore. šŸ˜…
Some of us would rather have peace of mind and variety in life, living as close to the edge as your time/lifes/budgit can swing. As hard as it can be for most, money can be replaced with hard work. But time once it passes? Is impossible to replace.
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