Tyler1986

Just picked up a 2004 GX with 155,000 miles. I have the complete service records from Lexus up to 120,000 miles.

- Drivetrain replaced at 40k (thumping)
- Timing Belt and Water Pump at 80k
- Brake fluid, Diff and Transfer fluids at 90k
- Airbags (suspension) at 100k

That is pretty much it from recorded history.

Coolant and Brake fluid looks clean, what should I look into having done from right now to 6 months from now (try to space out my preventive maintenance)?

Looking at:
Oil and Filter change
Coolant change
Brake fluid change
Transmission fluid change????
Diff. and Trans fluid change (possibly wait until I get new brakes put on along with new tires this summer)?????

Thanks!

Thanks.

chiph9

Best advice is to follow the schedule in the owner's manual.

However -- Lexus thinks the transmission fluid is "life of the vehicle" and lots of people have a problem with that. You can do an entire change by tapping into the transmission cooler line and letting the built-in pump swap the fluid for you (idle the truck for a few minutes until the exiting fluid runs clear as you add new fluid on the other side). Or you can do a drain + fill every 30,000 miles which will get about 1/3 of the fluid out. Do not do a "flush" as the pressures can damage the internal filter.

Chip H.

LoneHiker

You will want to get on a regular schedule of transmission fluid changes as mentioned by chiph9. There are writeups on this forum for how to do a partial fluid change and a complete fluid change using the transmission's pump.

Timing belt and water pump are due again at 170k, be sure not to miss that.

When you say "Drivetrain replaced at 40k (thumping)" you mean "driveshaft".

Other than that, it looks like you're in good shape for a long while.

2008

Make sure you lubricate the driveshaft soonest to make sure it hasn't been neglected for a while .. possible that was the case even if you have oil change receipts.

If the coolant is the correct color (red/pink), I wouldn't bother changing it until you do the timing belt job again. Otherwise flush with correct coolant. When you do the timing belt in however long you can replace the coolant. I got much more coolant out of the car than I was expecting when I drained from the radiator and freeze plugs so I didn't bother flushing afterwards. Don't think there was more than 15% of the old coolant left. I did remove and inspect the radiator and was able to drain an extra quart or so (after draining it while on the car using the plastic plug).

Make sure to change the transmission fluid.. I did this when I bought mine at 90k. I bought 12 quarts of toyota WS transmission fluid (kind of pricey). That should be good enough.. even if there's a little bit of the old stuff left. Changing the filter is probably a good idea too but I didn't bother when I did mine. I just drained the fluid from the transmission pan drain plug, filled to the top of the fill plug with new fluid, and used the return line to fill a gallon jug I had marked with a 2 QT line (to make sure the pan didn't run dry). I'd run the engine for not very long until the transmission fluid had drained to my container's fill line. Refill, repeat through 12 quarts of new fluid. Make sure to properly set the transmission fluid level after doing this. (draining excess when in the right temperature range indicated by either jumping obd pins or using techstream)

Keep a close eye on the coolant level for a while .. to make sure it's not leaking at all. Not uncommon to leak at the waterpump or develop a seeping leak from the radiator. One other GX I looked at when purchasing mine had no coolant in the reservoir, mine just started leaking measurably from the water pump before I did the timing belt job (which is why I did the job instead of procrastinating more). Even in a common timing belt job DIY the author's vehicle had a water pump leak.

Otherwise: Lubricate driveshaft on time, keep an eye out for signs of stuck front calipers, make sure the rear air suspension is working properly, if there's a good deal of surface rust on the undercarriage think about undercoating with fluidfilm or something .. these toyota frames seem to rust more than most.

Edit to add: 2004 engine isn't VVTI so it's not an interference engine. If money is tight or if you don't DIY, you can delay the timing belt job. Just make sure to keep an eye on coolant level if you do, no other great way to make sure the water pump isn't leaking (it's hidden behind the timing belt covers and the coolant cooks off into solid pink crud after seeping out).