Rear Differential Oil

[IS300FSPORT]

 

Greetings All,

I have been taking useful info from here since buying my car over a year ago but have not made any posts so here is my contrubution should it help anybody. If any of you plan on doing a DIY differential fluid change on an IS300H. Its a fairly straight forward job I have done mine at 50,000 miles on 2015 model it may well be the same on GS models too. Although my car has a full service history from Lexus none of the invoices listed the item no or job so in all honesty im not convinced its ever been checked or changed. The oil was fairly fresh Id say it could go on another 50k on normal use,  but for peace of mind and as I intend to keep the car long term I just changed it. I do appreciate some may argue its a lifetime fluid so why bother but the debris of the metal particles is what can cause a problem if left unattended. I didnt have much dirt stuck on the magnet either.

Tools required:

- 10mm Hex

- Brake Cleaner to wipe away old fluid

- Cloth/old rag

- Bucket to catch old fluid

- Extension and Ratchet

- Diff fluid 75w-85 GL5 1.3-1.4L so you need x2 1L bottles (part number 08885-81060) approx £17 a litre. Call it £35 with delivery from most retailers on eBay. 

- Fluid Transfer srynge/pump - £10 

- Wire brush

Steps involved 

*** Important & do so at your own risk ***

*Ideally the car must be level to get an accurare amount of fluid back in.

I drove the car onto a wooden step/ramp to lift it slightly at the front, leave it with the handbrake applied & in Park. Chock  the front wheels for extra pre-caution

jack up just under the rear differential to get it level, to the same height as the front & put 4 axle stands under the sills for safety.  However like me if you only have 2 axle stands put the 2 axle stands at the rear it is more important as you will be working at the rear of the vehicle.

Ensure the top plug is removed first this is the fill plug do not undo the drain plug without knowing you can refill! 

Then undo the drain plug at the bottom let it drain takes approx 10 minutes to drain. It has quite a strong smell like an old school garage. Once drained put the drain plug back on ideally with new gasket. Tighten up until its reasonably tight apologies I dont have the torque figure.

Refil the differential using the fluid transfer pump. Continue pumping until you get a steady flow dripping out until it becomes a drip. I used approx 1.4L the fill is upto the level of the drive shaft it will pour out once full so it cant really be overfilled unless you dont wait for the steady stream to turn into a drip.

I believe the dealer will charge in excess of £150+ so not a bad saving. Good luck its not a tough job just requires time & patience if you can do an engine oil change you can do this job. The recommended interval from reading on the internet is every 2nd oil inspect & refill as necessary & change fluid every 30k.

Hope this may help somebody someday.

 

[cadman2k]

Great guide, wondered if you'd ever thought on cleaning up the diff block? I believe it's common that they start to present a rusty appearance and that its surface corrosion. I guess the cleaning would only improve the aesthetics as any rust on here would take forever if at all to have any adverse effect on the component itself 

[IS300FSPORT]

Funny you should mention that I did consider getting a can of black spray paint on the diff case, but I didnt fancy doing a half hearted job. I'd need to wire brush all the surface rust off primer it & then spray it but that involves time & effort. I have seen plenty of high mileage GS models from the 90s none reported to have the case corrode away. So its just cosmetic doesnt bother me in all fairness. Once you start cleaning & spraying one area the rest of the under carriage looks corroded so where do you stop? Im ok with it looking like an honest car its not a garage queen so its going to have some form of wear showing as long as its presentable at MOT it does not bother me. 

[agent_dess]

Hope you replaced the crush washers 🙂

[IS300FSPORT]

It is best practise to use new washers.