Hello-I subscribe to the--If it aint broke-dont fix it theory.... Question: any info / opinions - - If or when to change my rear end fluid? -- Im sure its never been changed....What weight is best for summer driving? Use Conventional or Positive Additive? My slant runs like a dream -no issues -- 68,000 miles

Things like oil changes are to prevent stuff breaking. Yes, get some fresh new oil in there. Use a reputable brand of 75W90 or 80W90. No limited-slip additive is needed or beneficial unless your car has a Sure-Grip rear axle, which it probably doesn't because most of them didn't. Check by jacking up the back of the car, releasing the handbrake, and rotating one wheel. Other wheel turns the other direction? Not a Sure-Grip.

While you are at it, drain the transmission and torque converter, adjust the bands, replace the filter, and fill up with a reputable brand of Dexron-VI fluid. Info on new trans pan and gasket that make life easier here (written for earlier-year cars, but the pan and gasket are same).

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Totally agree with Dan. I cannot think that 52 yr old diff oil is still good.

Lou

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Home of Slant6-powered fun machines since 1988

Well, I got 500,000+mile running Tacoma with original rear end lube, and original rear drum brakes. I'm in So Fla and I often tow 5Klbs, but I'm the only driver, your results may differ.

Oldest your Tacoma could be is a 1995 model. Not only is that nearly three decades' less oxidation and condensation, but also the oils and greases and lubes of 1995 were light-years ahead of those of 1968.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.