1986 240 34,000 miles - synthetic oil for auto transmission?

Just bought a 1986 240 with 34,000 miles... I've been reading a lot of old posts, but they all refer to manual gearboxes, not automatic. There's no service records, so I'm going to to be renewing all fluids in the car. I'm wondering if I should put synthetic oil in the automatic gearbox?

I was considering synthetic engine oil. But a search turned up popular opinion is, there's not much benefit compared to the risk of developing leaks.

What about brake fluid... Is there anything I should avoid/be aware of? (I'll be going to mechanic who just uses the same brand on every car he services. Is there something I should be buying for the transmission/brakes that he wouldn't have?)

Reply to
thefamilyman
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Forgot to ask two other things:

I'm in Australia and we can only get unleaded fuel with ethanol now. I've been running my 1978 on the cheapest unleaded for years with no problem. Will the cheap stuff hurt the 1986, or should I be switching to premium unleaded?

Any recommendations for radiator coolant?

Reply to
thefamilyman

34,000 miles on a 25 year old car?!? Or is there a missing number?

The Volvo manual specifies the type of ATF to use, just use whatever is compatible with that.

IMHO don't bother.

Probably not. This stuff is all pretty standardized.

No. If anything the 86 will do better on that than the 78.

Check it with a hygrometer and look for contamination. If it's OK, why change it? As for coolant, most manufacturers have gone to a universal formulation with minor differences, so it's generally not necessary to consider matching colors and all that crap we used to be advised to do.

The only thing I would recommend is taking a really hard look at the wiring harness of the car. 240s of that age often have problems with crumbling insulation of the wires.

Reply to
Tim McNamara

synthetic transmission fluid just has better thermal characteristics, but if you're not racing it will never matter. remember teflon brake fluid that wouldn't mix? i don't think anyone still markets it. again the "dot" classification is mainly thermal. coolant is watered down in some of the warmer climates. i don't know about Oz.

Reply to
rwlangbauer

Reply to
John Robertson

Heh, it's 34k alright. I know it's correct too, due to things like: no dust at all in the air vents; plastic engine sump cover looks like brand new plastic when you look down from above (still cracked underneath of course); the cooling fan is immaculate - white and shiny like a brand new part has been fitted; and the metal clutch the fan bolts to is bright and shiny metal. I think you'd have to remove that from the car and polish it to get the same result. ;-p... I also peered into the rocker cover today when I did an oil change. Although the oil was close to had it, inside is mirror finish with no blackening.

The owners manual says "AFT Dextron II D." No idea what that means yet. The (greenish) Haynes manual says on page 10, "Automatic Transmission Fluid type F or G." Clear as mud!

I have had a look but I didn't want to tug on it too much. If it starts to happen I suppose I'm aware of it and can take steps. Has anyone replaced a wiring harness? Where on earth would I even find one... And being in Australia, surely something would be on the wrong side (since we drive on the other side of the road). I wonder if Australia even had this problem for that reason. i.e. Maybe we got different wiring harnesses down here.

Reply to
thefamilyman

happens. rv's are famous for low mileage. people use their vehicles in different ways.

"rocker"? cover. i think you have a cam shaft.

dextron II & type f definitely are not compatible. go w/ the owners manual! different ats were fitted. it should know what you got.

a wiring harness is not a single entity. there are separate bundles (of wires) running here & there (after passing through your bank account). i have never replaced a complete bundle. i have just done work arounds. Volvo can be persuaded to provide a diagram, that & experience seem to get the job done. (says an old fart) i loved Hayne's manuals when i was learning. look, pictures! what a novel idea. a replacement harness will come from Germany by way of the UK. handedness is not really that important, convenient, but no more.

Reply to
rwlangbauer

My '83 has the missing number. 340k miles.

Better yet, I recall reading in some manual use Type F unless the transmission has been rebuilt. Looked all around mine and didn't find a 'Rebuilt' sticker, so I'm using Type F. Been fine for 15 years and 150k miles.

Volvo might have solved the harness leprosy issue by '86, I dunno. Google is your friend. It's pretty obvious if the wires are bad. There is a plug at the firewall on the intake side of the motor that is one end of the harness. If the wires there are pristine, chances are it's a good harness. They will be black and crumbly and mostly bare if it's bad. I nursed my rotted harness for years until one day the starter pulled in at ~ 30mph. I caught it quick so I didn't lose a starter or starter ring. If it happens at highway speed, really bad things happen.

This guy is the guru of harnesses:

Replacing it is a (leisurely) days work. Moderate difficulty. Rebuilding it is an option if a good replacement can't be found. Lots of soldering and shrink tubing.

Reply to
clay

I have seen such a car ,a doctor brought it in to sell at the local Volvo service agent it had a scratch on the back mudguard/ fender where his old mum/ mom backed into something .Other wise it was like new, a fawn or pale blue 240 ,wouldn't be the same car by chance would it ?One old dear In Tasmania brought a new car and would be lucky to have put many klm on it as she only drove to Worship .Mary died a few years later and I doubt if the car needed it's first oil change . As for synthetic oil look in the rocker cover of a car that's run synthetic oil and it will be clean as.I have seen older cars with normal oil full of crud around the filler cap internals which you could scrape off. aft dextron 4 is now the current tranny oil .

Reply to
John Robertson

I'd call it a valve cover.

Reply to
Tim McNamara

Reply to
rwlangbauer

my niece would call it "that carbon fiber thingy that goes on top." we don't send her to the store.

Reply to
rwlangbauer

to finish up a thought. e. glycol & additives do more than change the thermal properties of water. ~50/50 is the right blend. yes, you can run on pure H2O or even urine (think Volvo/Penta), but your engine will not be happy.

Reply to
rwlangbauer

LOL!

Reply to
Tim McNamara

I've doing some reading... (IPD, old messages here, a couple of Volvo forums.) IPD sells a hose to drain the auto transmission yourself. The general consensus is to drain while the oil is hot/warm. And in the instructions for their hose, IPD state: "We advise that you only do 1-2 quarts at a time."

Do they mean to drain 1-2 quarts, then turn the engine off and add 1-2 quarts back in again, then start the engine and drain the next 1-2 quarts?

The reason I'm scratching my head over it is, I read somewhere that hot transmission fluid "expands quite a bit". If that's true, then you wouldn't want to add back in, the same amount that you drained out, would you? (Wouldn't that mean you end up with an overfilled gearbox?)

Reply to
thefamilyman

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