2003 Tacoma: 80W-90 for Diff AND Transmission?

I had that same problem. I recommend you sell your vehicle immediately and buy a new one.

Worked for me.

OK....thanks.

Now, does anyone out there who ISN'T 3 sheets to the wind care to offer an informed opinion????????

Josh wrote in news:60636811-db17-41f0-b150- snipped-for-privacy@u8g2000vby.googlegroups.com:

The primary thing here isn't the weight, but hypoid versus non-hypoid.

Your diff *MUST* use hypoid lubricant. Your transmission *MUST NOT* use hypoid lubricant.

And if you're forced into two different lubes anyway, you might as well use the correct stuff in each.

This makes sense since it needs that high pressure additive.

Why not? Why does the high pressure stuff do any harm? There aren't any bronze bushings or anything, right?

--scott

a lot of synchros use brass or bronze cones. some gear journals too.

if synchros are "too lubricated", they don't sync, and gears grind.

as others say, it's not simply a matter of weight. but the bottom line is money - how much does a transmission or diff cost vs. a pint or two of the correct grade lube?

Those EP lubricants, usually based on sulfur compounds, are as slick as owl snot. I dont think auto trannies are made with these in mind. Mechanical gearboxes might thrive on them.. Just my $.02 of uneducated comment.

Yeah, I thought we were talking only mechanical gearboxes, not the slushboxes. I don't see any reason why the EP additives would be bad in a manual unless it did have bronze bushings for synchronizers or the like... and if it did, they would be eaten away pretty fast...

--scott

ep additives wouldn't "eat" them away - it would lubricate the cone clutches [in that kind of] synchro so they didn't clutch properly. if they don't clutch, then the gear meshing dogs grind.

and please don't call automatics "slushboxes" - they're highly sophisticated and [generally] highly accomplished pieces of engineering. such a derogatory term is both inappropriate and perpetuates ignorance about their operation.

snipped-for-privacy@panix.com (Scott Dorsey) wrote in news:ic1s0j$pen$1 @panix2.panix.com:

Synchros. Hypoid lubricants mess with their frictional properties. You can get grinding and difficulty getting the lever into gear.

Mitsubishi manual transmissions spec hypoid gear oil and contain bronze looking syncro cones.

Bret wrote in news:14ba52w673vfc$. snipped-for-privacy@40tude.net:

Then the synchros are designed for use with hypoid, which is not common practice, from what (I think) I know.

In any case, the OP's gearbox was not designed for use with hypoid, while his diff was, so whatever Mitsu does is not relevant to what the OP's Toyota needs.

Absolutely.

This says for an 03 Tacoma API GL-4 or GL-5

Seems to be allowed, does the manual say API GL-5 is ok in the transmission.

IMHO no.

OP here.

It looks like the consensus of you guys is that the Quaker State

As for the trans, I forgot to mention my manual recommends:

OIL TYPE: Gear Oil API GL-4 or GL-5, Viscosity 75W-90

The Quaker State 80W-90 GL-5 bottle label says "It is suitable for make-up or refill fluid in those applications specifying an API, GL-5 , Mt-1 gear lubricant such as manual transmission and conventional and Ltd slip differentials". It also says it provides extreme protection for hyphoid gears.

Since the oil already in my trans is API GL-4 or 5, and Quaker State says this stuff is suitable for refilling transmissions specifying API, GL-5 lubricant, it looks like the QS is OK for my trans. But I'm still not clear as to whether this QS 80W-90 is technically a HYPHOID lubricant, or just one that will work with hyphoid gears.

He said it was a 5 speed, but at first I assumed it could be automatic. I dont even know if they have an auto 5speed for that vehicle. But like you, if it were a manual, it probably wouldnt be much of a problem. That is what I get for assuming.

Josh wrote in news: snipped-for-privacy@j9g2000vbr.googlegroups.com:

I just checked with a Toyota MDT Tech I know. Apparently I'm wrong: That lube will in fact be just fine for use in both your tranny and your diff. He says they've been using GL-5 for years with no problems.

The only real hitch is that in cold weather you may find shifting to be a bit stiff, and in that case you just warm the engine up a bit to allow its heat to soak into the tranny before driving off.

Could be. Thing is, the EP additives are sulfur compounds that form sulfur complexes on the surface of steel. This is a kind of corrosion, but it's a kind of corrosion that prevents galling and greatly improves lubrication performance at high pressures.

Unfortunately those additives will cause uncontrolled corrosion on some copper alloys. I have seen film projector gearboxes where people replaced the turbine oil with similar viscosity gear oil, and it literally dissolved brass and bronze parts.

--scott

snipped-for-privacy@panix.com (Scott Dorsey) wrote in news:ic66ic$754$ snipped-for-privacy@panix2.panix.com:

In the case of the OP, a Toyota MDT Tech told me the OP's chosen GL-5 oil will do just fine in both tranny and diff. He might encounter slightly- stiff shifting in cold weather, but that's not a big deal.