I'm 16 years old and this is my first car so I'm very lacking in experience anyways recently I re did my front suspension we're talking everything new upper and lower control arms new brakes new hubs new CVS new dust shields new ball joints. Just last night I was driving home and I started to hear a knocking noise coming through the floor I thought it might be a drive shaft with my limited experience so I was just curious if there are any lexus geniuses on here that can help me out

 

Nice work for 16! If you’re hearing a knock, double-check that everything’s torqued properly especially control arms, ball joints, and CV axles. Could also be loose sway bar links or something not seated right. An alignment after all that work is a good idea too. Let us know when the noise happens exactly!

 

Does it happen at any particular speed or during acceleration/deceleration?

Chip H.

 

it happens on decel right when I let off the gas and before I hit the brakes

 

Check the driveshaft bolts are tight and the u-joints don't have a lot of play in them when hand turning the drive shaft back and forth maybe? Have you lubed the driveshaft u-joints and yoke yet? Did you ever hear the knocking before doing all that work? If not, I would really focus on the areas you touched to make sure everything is torqued down properly.

 

The early GX models had a TSB about worn splines on the rear driveshaft. There was an updated part released (TSB, not a recall. So Lexus doesn't pay)

But first - when was the last time you greased the driveshaft fittings? There are greasing points on the universal joints but also on the splines where the slip joint is. Do that first. And every 30k miles.

Chip H.

 

Since you are clearly going to do a lot of maintenance yourself, if you haven't already been referred to "The Car Care Nut" (TCCN) channel on YouTube, it is a must - search for videos of things on GXs and LXs and you'll find some very useful information. Also look up the "Car Wizard" and search for his GX470 videos, which will provide some good info too.

The one I saw this week on TCCN, going over a 2014 and a 2023 GX, which has a lot of carry-over or similar components to the GX470, referred to a clunking sound that can show up when you fail to lubricate the driveshaft, as previously mentioned. There are at least two grease zerks (google it to be sure you got them all), but it warned about over-greasing them also, as it will sling the excess all over the place, so if it happens you'll need to clean it up so you don't confuse it with any other (future) leaks.

If it's any encouragement, after a TON of research I found my son a very low mileage (unicorn) '07 GX470 and he loves it. I consequently bought a 2019 with 74K miles, which is higher mileage than his. However, his roommates have an '04 with over 400K miles and a '13 with nearly 250K on them and they still love them, so with the right care, you'll probably have it for many years.

This is a great sight to watch, as there is a lot of combined knowledge and wisdom here. Good luck!!!

NOTE: A couple of other good YouTube sites, if you're tempted to modify your rig:
Tinkerer's Adventure - Goes into the pros and cons of lifting your rig
Tandem Offroad (in DFW area), that shows you how they modify and lift different Toyota products