I got my 91 fj80 Jan 1 290k. Oil pressure seems low. I want to give it some lovin' but I don't want to do anything stupid. Was reading about dropping 4 qts of oil and replacing with atf to clean sludge and restore pressure. Any thoughts?
Oil pressure? Engine ATF flush?
- Thread starter 91fj newbie
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That does sound kinda stupid.
Why would that be a good idea? There has to be some reasoning to it if they are recommending it. Otherwise, I feel like that might be a prank. If you want clean oil, just change it a lot with a new filter, Rotella and other diesel oils will clean up your motor in no time.
Why would that be a good idea? There has to be some reasoning to it if they are recommending it. Otherwise, I feel like that might be a prank. If you want clean oil, just change it a lot with a new filter, Rotella and other diesel oils will clean up your motor in no time.
Before you do anything drastic I'd recommend measuring the oil pressure compared to the service manual specs so that you have more info than it "feels low".
Do you hear any noises that would indicate low oil pressure? When is the last time the oil was changed?
Do you hear any noises that would indicate low oil pressure? When is the last time the oil was changed?
Absolutely NOT.
Just run clean, standard oil and do early, regular oil changes.
Don't do ATF, Kerosene, Diesel Fuel, or Seafoam in your crankcase. It is made for OIL that has the proper viscosity, lubricity, and cooling properties for your engine.
Use a quality oil filter (Not Fram).
Why a diesel oil in a gas truck?
Just change your oil and enjoy the ride....If you want your oil pressure high for whatever reason throw some 20W-50 in there.
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What I read was that the detergents in at will clean out gunk in the engine. Oil pressure needle sits at 1st mark on gauge-approx. 1/3 up the gauge.
I wouldn't trust the gauge as absolute fact. It's pretty much a dummie gauge.
Seems normal to me
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- #11
Cool. I really appreciate the input. Looks like you guys saved me from myself. Also how do you get an accurate oil pressure measurement?
For an accurate measurement you'll need an external gauge. This instruction is for the FZJ80 rather than your FJ80 but will be very similar.
I have an Issopro gauge in my rig and like it.
Because they have higher levels of detergents in them. The downside is that running diesel oil will do damage to your cats and in my experience, it's too thick at the 15w40 that is most commonly available in my ass cold environment.
My personal suspicion is that the detergents in the diesel oil loosen a ton of sludge and other gunk and then that gets blown all over the cats and they get clogged. If I were planning on a new exhaust system, I would run like three batches of Rotella through my rig and then do the exhaust job and then I would just switch to normal 10w30.
There is a metric f-ton of info out there on oils, but the bottom line is that if you run at short change intervals with standards meeting oil, you will clean the internal parts over time.
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You guys are an amazing resource thank you!
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- #16
Any thoughts on additives-marvel mystery oil et al?
Don't worry about additives etc... focus on clean oil with shorter change intervals if your goal is to clean up the inside of the engine.
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- #18
Thanks
What mile interval are you guys using????
Oh and where are pics of your new 80? Welcome to the club.