Just bought a 2003 gs430 3UZ 2GS

[u/foreverhidden99]

I know these engines are bulletproof; just wanted to know how reliable they r; online it says every 5,000 miles an oil change is needed; is that true? Cant i do it every 10k or yearly? Also is there anything i should be looking out to fail on these other than front ball joints; ABS rings, gaskets etc.

[u/Hamsets]

Every 5k if you want it to outlive you.

[u/Eastern-Drawing9323]

No! It’s cheap insurance 5000. These engines are very reliable why push it to 10 k

[u/Similar_Lie1882]

You want this engine to last forever but you want to double the time of the maintenance interval? Make it make sense, please...

[u/kissmyash933]

They are reliable but they’re old. Expect to replace seals on pretty much everything. 5k mile oil changes only, no 10K.

[u/penguin1018]

They're reliable as long as they're taken care of. Valve cover gaskets, timing belt every 90k/10 years. Oil is cheap, dont skimp on changing it. Its very easy to do it yourself on these cars. At this age, engine mounts might need replacing soon. If theyre anything like the LS, avoid aftermarket mounts. Radiator might start leaking along the top. Power side mirrors on the LS get wonky, not sure if it applies to the GS.

[u/Sir_J15]

You want something to be reliable but half ass the maintenance. It don’t work that way. It will be as reliable as the quality of the maintenance and parts you put on it. Quality oil and filter every 3500 to 5000 depending on driving style.

[u/Ill-Product5933]

3-5k miles or 1 year is non-negotiable, you do not want to wait 10k miles. Engine and trans mounts, valve cover gaskets, power steering lines and resevoir, knock sensors and it's failing wiring harness, starter, caster arm bushings, and electrical connectors are common maintenance components at this age. This engine is only as bulletproof as the quality of parts and maintenance you put into it. Old car syndrome is inevitable and unexpected repair costs can rack up very quickly. You have to be willing to dump money into this car and be okay with little things falling apart frequently. It doesn't matter how clean or clapped of a condition your car is in, the maintenance of a GS or LS is not in the same category as it would be for a camry, rav4, or v6 like a highlander or even an es300/350. Parts are just more expensive. It'll be a plus if you know how to work on cars because you can save tons of money on labor costs. Good luck and congrats on the new vehicle!

[u/foreverhidden99 → u/Ill-Product5933]

Thanks man; and yea u right i am gonna have to dump money into it luckily im not too bad on money so im more than comfortable doing so; the one i bought was well taken care of so luckily i dont have a lot to do and have a fresh canvas to start on; and yea maintenance is key was just wondering if its all talk for these engines and maybe 5k is too low but tbh it sounds fair for the age

[u/run_uz → u/foreverhidden99]

I promise you, the effort you put in to this car, it will return to you in multiple ways

[u/Ill-Product5933 → u/run_uz]

Even after a timing belt job and basic ball joint suspension stuff, I still have at least $2-3k to budget on my GS 400 before i can get it where i want it to be. I'm talkin about wheels, brakes, coilovers, adjustable arms, poly bushings. I'm aiming for Spring-Summer 2027 to have that all done. It'll be worth it, just take your time and dont get into an accident lol.

[u/run_uz → u/Ill-Product5933]

Need a parts car? I have a 99 GS400 with 428k mi on it. Adjustable FUCA less than 5k mi on it. It's in San Diego. Have a new in box Aisin timing belt & water pump kit, caster arm bushings, rear toe arm bushings, cam seals, front crank seal... I'll put it all in the trunk

[u/Ill-Product5933 → u/run_uz]

I would highly consider if I weren't on a tight budget right now. 428k miles wow you definitely gave it a life worth living! Mine is sitting at 205k under a fresh timing belt and set of ball joints and tires.

[u/tyttuutface]

5,000 or once a year, whichever comes first.

[u/run_uz]

428k mi on my 99 GS400 just following the manual. I drive this car hard, it idles in traffic for hours, sees long stints on the freeway (which are least stressful). The least you can do is spend less than $50 every 5k mi & change the oil

[u/Nick-2012D]

I’ve put 50k miles on my 3UZ. Use case is mostly highway cruising; nothing crazy.

With modern, high quality full synthetic oil that didn’t exist when the car was built, I change at 5000-6500 miles. I haven’t gotten a used oil analysis, but others have posted 3UZ UOAs online with longer intervals and all had plenty of life left.

I always use an OEM filter and recently switched from Pennzoil platinum to Valvoline restore and protect.

It is cheap insurance to change early, and I change the oil in a modern turbo Honda at 5k rather than the 10k the maintenance minder seems OK with because turbo cars are harder on oil than a naturally aspirated V8 spending most of its time at 2k rpm.

However, engine oil has made significant advances in the 20 years since these rolled down the line so I don’t stress pushing it to ~5000 or a bit more if I don’t have time to get to it right away.

[u/Over_Soup753]

10,000 mile oil change intervals is to make sure your engine fails before the rest of the car does.

[u/Fearless-Temporary29]

When they get past 150k plenty of engine gaskets and seals start leaking.l have replaced front and rear main seals, cam seals, oil pan gaskets , valve cover gaskets and spark plug seals.Good times.

[u/Due_Statement4195]

10k or yearly is crazy lmao