Off of work this week with some time on my hands so I am working some projects on the cars. I put the LS up on ramps and opened up the diff fill bolt to make sure it would come loose in preparation for removing the diff drain plug and changing out the rear diff fluid. Since the car was not level some diff fluid starting coming out of the fill bolt hole as I loosened the fill bolt. To my surprise the fluid was absolutely clear and brand new looking after 20k miles. So I cleaned the plug, reversed the crush washer, and put the fill bolt back in. I will wait another 15-20K or so before checking again. My car has 50K miles on it now. The diff fluid was changed from the OEM factory fill at about 29.7k. I have read that first OEM factory fill change is important to get the metal wear gunk and shards out but later changes are not as critical. My guess is that the second fill will easily go 50-75k before next change is required. So I drained and filled the Toyota Highlander AT instead - 4 quarts of Toyota long life AT fluid. So easy on the Highlander don't even need a jack to change AT or engine oil on that one. Getting under the LS without jacks or ramps is impossible.

 

Even on ramps how much room do you have? Thanks

 

Draining and refilling a differential with only 20k miles that's already had the fluid changed before would almost be the equivalent of changing your motor oil every 1k miles.

I easily think you could go 80k miles and it would still be OCD. People that change differential fluid a lot are usually 4x4's that are offroad all the time and are immersed in mud and water.

I would though love to buy my next used car off of you, I bet your cars look and run perfect when it's time to sell.

 

30K is a very short interval. I had done the LS400 at 50K and the fluid came out very clean. Having an analysis would indicate actual lubricity package values for the miles driven. Differential issues don't seem to be common among the 400 or 430's with minimal intervals. That's saying a drain at 100-120K miles though not advised.

 

Yep I'm guilty of over maintaining my cars a little, but its basically a fairly inexpensive hobby for me to do my own light maintenance. I have sold maybe 10-12 cars over the years and in every case but one the first person that has come to look at the car purchased it on the spot. In the one exception case the first person said they wanted to look at some more cars, and the second person that came to check it out bought it.

And in reply to warminwisc question on ramps - my hand built ramps (really tire cribs - laminated 2x12s and 3/4 plywood sandwiched) are about 4.5 inches high. Doesn't sound like much but its enough for me to easily work under the front and rear of the car. Always used with 5lb solid rubber chocks on each wheel of other axle. I have a 6k lb hydraulic floor jack that makes quick work of lifting the corners on the LS.