So the other day I had all fluids changed out. Rear diff had some small metal shavings on bottom drain plug. How worried should I be? How long till it completely craps out on me? What is the best way to repair or replace it?
Rear Differential
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As above some metal 'dust' on the plug is normal. I probably pull about a gram or about .5 teaspoon off the magnetic drain plug once per year. When the 4.88 gear set was new and going through its break-in process it was more...
If the rear diff factory locked? If so, I would not worry too much. If it an after market diff, I'd be slightly concerned. Any idea if your diff is generating any extra heat? Might compare temp on front to rear?? If you need to replace at some point, the 3rd is very easy to swap out.
If it'd never been changed before, it could have just been a piece left over from machining or the orginial break in. I wouldn't worry about it unless you have noise or heat back there.
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The rear diff does have a factory locker installed. I know the diff fluid has been changed at least once by me in the last 50,000 miles. I am going to ask one question that is going to show my lack of automotive knowledge. The rear diff on the LC with a factory locker is NOT a limited slip differential, right? For some reason I thought my diff was a limited slip differential but the mechanic said it was not. I am assuming that you would not have a limited slip diff and a factory locker installed on the same diff, but I do not know.
Trunk Monkey
Moderator
It is a selectable electric locker and only activated by the switch on the dash (the rotary one left of the steering wheel). You do NOT have a limited slip. A LSD does not require driver action to activate, just difference in wheel slip.
131.5*. 131.6 and you're screwed, everything will lock up.
131.5*. 131.6 and you're screwed, everything will lock up.
It depends on load, ambient temp and oil type. I would think 180 would be pretty normal for dino oil on a 80degree day. I normally add 100 degrees to ambient temp for expected oil temp. A few degrees less if full synthetic. New or incorrectly setup gears will be well above 230. If you are using an IR thermometer, you'll need to account add about 50 degrees to the diff housing temp. This is farily inaccurate, but on an AWD vehicle with removable 3rd members you'll be able to understand the temp differential between front and read diff.
Thanks, I'll check mine. I know you have to change the oil every 30K (per book), and a little more if you wheel it (so the stealership says). I'm right at 28K and been wheeling the hell out of it including some water crossings. I hope I haven't done damage to anything, I know I have a very slight grinding noise from the front diff under heavy load going up hill only. I have started to lift of the gas when it s***s to reduce load on it (I put it in low going up short hills so it won't shift). I'm getting everything changed this weekend and will take pictures. Hoping there isn't chunks of metal or a huge amount of shavings on the magnet
RU sure the grinding noise isn't the transfer case TSB? My 100 grinds a bit through the 4-hi-lo shifter when going up a hill, low RPMs - my understanding is that it is fairly normal.
BTW: not to hijack the thread, but my 100 has 88K on it and I wanted to change from conventional gear lube to synthetic. I called Amsoil rep. and was advised not to unless it was well-maintained. I purchased used at 84K, I don't know what the maintenance was. I was planning on changing over wife's Lexus RX 300 (103K) as well - those transaxles seem to get hot, therefore syn. would be better. I would not hesitate to put syn. motor oil in, is syn. gear oil's properties different?
BTW: not to hijack the thread, but my 100 has 88K on it and I wanted to change from conventional gear lube to synthetic. I called Amsoil rep. and was advised not to unless it was well-maintained. I purchased used at 84K, I don't know what the maintenance was. I was planning on changing over wife's Lexus RX 300 (103K) as well - those transaxles seem to get hot, therefore syn. would be better. I would not hesitate to put syn. motor oil in, is syn. gear oil's properties different?
I wouldn't worry about switching to synthetic...advantages will include much longer service life, better protection in warm weather and a lower minimum temperature rating. Downside is cost. If you plan on keeping your cruiser around for a while, synthetic is a given...both diffs, xfer case, & engine
Steve
Did the Amsoil rep say why he would not change to synthetic unless properly maintained? Seems weird.
I believe he mentioned weeping, or seals as a possible issue (if not properly maintained)...I thought that was a popular urban legend w/ synthetics, however, maybe I'm wrong. Other than that, nothing.
Interestingly enough, Amsoil's gear oil is about 1/2 of all the other name brand syns. I can buy locally through retail routes (RP = $18/qt.). I haven't ever used Amsoil, but it seems like a legit. contender based on the raving reviews it always receives.
FYI: I use M1 0W-40 syn. in the engine.
I'm having a pinion seal on the rear diff. looked at this Wed. - I'll take pics. (it is weeping) and post the problem and, hopefully, solution for everyone.
Anthony.L
Looking for the end of the road...
0W-40 sounds WAY too light. Toyota calls for 5W-30, any good reason why you are not following their specs?
For engine oil, it is slightly heavy at operating temp. A lot of performance engines run this weight due to its wide spectrum of operating performance. For a v-8 operating in both cold and hot environments, its a good choice. Also, a lot of people run Shell's full synthetic 5w-40 rotella.
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synthetic is a given...both diffs, xfer case, & engine
Why stop there? I also flushed out my transmission with Mobil1 ATF, and grease all zircs and packed front bearings with M1 grease.
Yes I'm a M1 fan boy. Mainly because I want syns, and can get the engine oil at (ahem) WalMart in 5 qt jugs for around $22 these days, and I wanted to standardize to one brand. I get the rest of the products from AutoZone locally as WM does not stock them.
Changed my fluids today, not too much shaving. Looked normal, when I had it on the rack I noticed my passenger side wheel had a TON of play in it. Looked like I found the source of my grind and vibration. Grease the driveshafts because they were dry as hell (literally) and my rear end squeak went away a little. Still have a bunch of creaks and squeaks under there
