Wow, only 3,100 RPM on the hiway.  Mine is more like 4,200 |removethispart|@ 70 MPH.

A lighter weight oil gives less protection than the heaver ones.  

I'm sorry but this is not true. Maybe back in the day but not now.
My dad is an old school machanic and he believes that the thicker the oil the better the protection. He killed 3 (THREE) 4.2 liter Jeep engines running 20w-50 oil. He even blew his oil filter OFF the block one time and still keeped using the heavy oil thinking it was something else.
He tried running it in his EFI Mercreiuser boat engines and finnaly figured out why they keeped bringing them selves down to low RPMs. They where protecting them selves because the were starving for oil. The thick oil was having trouble flowing through the filter, and to make it worse he was mixing it with airplane grade oil thinking thicker was better protection.
By the way he lives in Tortola British V.I. where there is no such thing as winter and going up the hills feels like your seated in the space shuttle preparing for take off.
Following him   I killed my Jeep engine. At first the lifters started tapping, then the rear main started thumping, and finally the #5 connecting rod came through the oil pan!

If you look at heavier weighted oil you'll notice there is NO star burst symbol on the bottles. NOT recomended for use in gasoline engines! I think it starts as low as 10w-40 or 15w-40. When I replaced the engine I used the recomended 10w-30 and never had a lubrication problem after that. Even in a place that never gets below 78*.

I agree

5W-30 is what I have always used and will always use.  I changed my oil every 3000 miles so there is always fresh stuff flowing in there.

on Dec 16th, 2003, 4:07pm,TN_Tracker wrote: Let me know how it does.

I will try.  My stupid exhaust pipes and muffler are leaking like hell so it's kind of hard to hear.

All you need to know about oil and what weight to use:

http://www.overboost.com/story.asp?id=1092

If heaver weight oil doesn't work better then why are we using 90w gear lub in our trans and diffs?

A heaver weight oil IS better at protect moving metal parts!  As like most stuff bigger or biggest is not always better.  It depends on the application.

As for today engines, no we don't need as heavy oil as we us to.  But that's due to engine design and better tolerances.

Engines of old had gear on gear oil pumps.  



Today engines have a rotory design.  They run off the crank shaft and not the cam shaft.  So they run twice as fast, and can pump out more pressure and volume.  So the heaver weight oils are not needed.



Factory is 5w-30.  That means when it's cold out the oil will be around a 5 weighted oil.  When it's hot it will be around 30.

Like I said earlyer, I run 15W-40.  It's a little thicker in the morning (153,000 miles things will have a little more wear on them) and at temp I have just an additional thickness if needed.  Just because it can go up to 40 doesn't mean it will.

If I had a newer engine I'd run something a little thiner

If heaver weight oil doesn't work better then why are we using 90w gear lub in our trans and diffs?

As like most stuff bigger or biggest is not always better.  It depends on the application.

As for today engines, no we don't need as heavy oil as we us to.  But that's due to engine design and better tolerances.

Engines of old had gear on gear oil pumps.  



Today engines have a rotory design.  They run off the crank shaft and not the cam shaft.  So they run twice as fast, and can pump out more pressure and volume.  So the heaver weight oils are not needed.



Factory is 5w-30.  That means when it's cold out the oil will be around a 5 weighted oil.  When it's hot it will be around 30.

Like I said earlyer, I run 15W-40.  It's a little thicker in the morning (153,000 miles things will have a little more wear on them) and at temp I have just an additional thickness if needed.  Just because it can go up to 40 doesn't mean it will. If I had a newer engine I'd run something a little thiner

I thought we were taking about engines? Where did tran's and diff's come in to this? Some manual trans require A/T fluid or 5w-30 to perform correctly ie; the newer Mustangs take A/T fluid in the manual tran's.

You answered your own question.
Like I said (I) drive a 2000 Tracker. It runs hydrolic lifters, hydrolic timing chain adjusters and the chain guides are made of a composite material, run heavy oil and you'll be replacing these parts quickly.

Like YOU said, "it depends on the application!"
If it's working for YOU keep doeing it no one is knocking your hustle, I know I ain't!

Have a smurfy day ......

 

Just a few points here.  

The demands on a gear oil are very different than those of an engine oil.   Manual Transmissions and Diff's (typically) don't have any sort of circulation system like an engine does and as such the higher viscosity is there to make the oil cling to the surfaces since it's not supplied externally.  

Automatics are different too in that aside from being a lubricant the oil is also acting as hydraulic fluid which means it's subjected to higher pressures and temperatures.  In order to get it to flow for hydraulic purposes it of course is a thinner viscocity than regular gear oil is.

As far as the Mobil1 filter, the reason it's better for lifter noise is that aside from being a very good filter when it comes to picking up small particles, it also is very efficient when it comes to allowing fluid to flow through the element. (much like a K&N air filter compared to a paper peice of crap).   I've been using the Mobil1 for a long time and for being fairly easy to come by it is an excellent filter.

The Napa Gold filters (Wix) are nice, but from what I've read they can't match the flow rates of the Mobil1. (about half the flow rate in fact) They do a great job of picking up contaminants though but honestly I'd rather have both good flow and filtering as clean oil that isn't getting to where it needs to be isn't much help.

Someone else mentioned Royal Purple and Amsoil as being the best Synthetics which is true.  Not sure where you can generally buy the royal purple, and the whole Amsoil marketing and distribution method bothers me. (Sorta like Amway even though there isn't any actual connection other than the fact they both start with Am).  No offense intended to any of you if you're an Amsoil dealer, I wouldn't buy Tupperware, Mary Kay or Avon either for the same reason if I had reason to need that sort of product, the whole practice just seems sorta shady to me. (plus the world doesn't need any more damn pink Cadillacs on the road anyway).

RedLine is also excellent but at 8 bucks a quart it is a bit spendy.  From some stuff I read on the boards for my VW, the additive packages in Redline oil are outstanding.  The other downside is availability.  I know the speed shops by me carry it but for the sake of being able to go to any normal auto parts store and pick up some Mobil1, that's why I use Mobil1.  I do use Redline Gear oils though.   I figure that gear oils with the longer changing interval are probably a safe bet using the 8 bucks a quart stuff.   (plus since I tend to have to add a quart every 1500 miles or so the 8 bucks a quart motor oil gets a bit expensive)  If you don't go through oil other than changing it though give the Redline oils a look.  Make sure you get the stuff for Street driven cars though, they make a race only line of oil that doesn't have any detergents in it which is fine on a race engine that's torn down frequently but on a street engine it's not a good move at all.

Supposedly the German Castrol Syntex is as good or better than Mobil1 but the US spec stuff isn't.  Gotta buy that from an importer though.

Pennzoil in any way shape or form should be avoided as should Quaker State.  Valvoline's not bad though for Dino oil, not sure about their synthetic though, haven't really heard much one way or the other on it.

One last possibility for those wanting to run synthetic on the cheap.  Some Wal-Marts carry Shell Rotella-T which is designed for diesel trucks with turbos and it is like 12 bucks a gallon if they have it.  It's not mass marketed so that's why it's cheap.  I believe it only sells in 15w-50 though or something like that.  It is SH rated oil for Gasoline engines but it's main market is for Diesels.  I've heard a lot of people using the VW/Audi 1.8 turbo 20v engine run it without problems though. (Speaking of which that's a kickass little engine, wish I could find a wrecked Passat to swap one out of into the Tracker) 170HP and a flat torque curve from about 1500-5000 RPM, and we get about 31 MPG on the highway with it in our Passat.

Anyway that's my spiel on oil and filters.

Good to be back in case anyone's wondering why I've been so quiet lately, been out of town on a vacation.

I only brought rear ends into the mix because you have metal parts under high stress.  Yes, they don't have a pump but they're in an oil bath.  The higher weight oil is used to keep the parts from touching and causing damage to eachother.

There are a lot of parts in the engine that are not under oil pressure but still need the protection of a good oil.

I've run Moble 1 (15W-40) in by off road vehicles (dune buggy and tracker) for 14 years under extreem conditions.

Haven't touched either engine in thouse 14 years (4 year for the tracker and 14 years for the buggy).

Wow, only 3,100 RPM on the hiway.  Mine is more like 4,200 |removethispart|@ 70 MPH.

I call it twisting the hamster's tail when I run it hard on the highway.  NOt redline, but close.

Well I changed my oil yesterday with some fresh Mobil 1 5W-30 and the new K&N Gold Oil Filter HP-1002 and to be honest I can't really tell the difference.  I don't really know what to look and hear for but at leat I know that this K&N is doing a WAY better job then the krusty Frams I was using.

Where did you find the K&N filter?

At my local Canadian Tire store.  It's Canada's automotive retail chain, amongst other things they sell...their more like a department store now, but they specialize in all things automotive.