Convince me not to use cheap conventional gear oil

Seems right to me that Pennzoil would make a video marketing a product the sell for more than twice as much.

 

but you see, that's the red herring people get hung up on, its not about what you pay for that one oil change but rather what you spend each year.

if you use dino oil and change it every 3 months you do 4 oil changes a year but if you use synthetic your only going to need half that many oil changes so you only need 2 oil changes per year. in short 4 oil changes at $15 = $60 a year for dino oil, or use synthetic and you do 2 oil changes at $30 = $60 a year so you spend the same money and have to change oil less often plus have extra engine protection for any extreme conditions. dino oil costs you $60 a year for oil changes and synthetic oil costs you $690 a year for oil changes.

so yes, while it sells for twice as much but you only use half as much of it so you still spend the exact same amount.

if you drive a car you don't have any need for synthetic oil

if you drive a truck and use it like a car and don't pull a trailer or haul anything ever then you don't have any need for synthetic oil

if you drive a truck and use it as a truck and never know when you might be hauling stuff or pulling a trailer then you need synthetic oil

if you have a 4wd then you need synthetic oil because 4wd run hotter so it doesn't really matter if you use it as a truck or a pavement princess

 

I'll throw two cents into this, I look at it this way, I've got one truck, and it's my baby, and I'm not going to cut corners on lubricants or anything else when it comes to it. Automotive products, including lubricant, tires etc. have came a long way in the last ninty years and I'm going to use the latest that technology has to offer. If you spread that 139.00 over the two years or so, till your next gear oil change, it's not that big a deal. It's not something you are changing every five k miles like engine oil. I may cut corners on somethings in life, but not when it comes to my truck.

 

Keaker, I actually just now found time to watch the 2nd video. I completely agree with those gentlemen (who I'm sure are much more qualified than me to make such judgement calls). I will note that they themselves question the wisdom of drastically extending change intervals on synthetics b/w 4:00 & 5:00 min. I think it all comes down to how we use our trucks and how confident we are that we'll get the fluids changed at the appropriate intervals.

Michael Roberts, I understand what you're saying but I have to draw the line somewhere. I could justify a lot of purchases I don't have to have with that reasoning.

This has been some great discourse, everyone. A lot of good points from both sides and a lot to ponder.

Edit: @Keaker, what do you mean "4WD run hotter?" I'm not aware that either the drivetrain or engine of a 4WD vehicle will run at any higher temperature than its 2WD counterpart.

 

I couldn't decide on what to use so I just stopped driving my truck.

 

yes they do, that is why they have coolers for the power steering and extra oil coolers and larger radiators and im sure there are other things too.

to drive both axles it puts more strain and load on the engine and drivetrain and everything associated with it and the more stress you put on an engine the more heat it builds up and in 4wd mode you are almost always off road in muddy, dirty, dusty, areas going slow and don't have the highway speed to push air through to cool things plus throw some mud on that radiator and your going to be running hotter temps then normal a lot of the time. so it runs hotter and its much harder for it to get rid of that heat and that's why you need extra cooling for everything. now in 2wd mode it probably runs just as cool or even cooler then 2wd because it has all the added extra cooling provisions.

I am not saying 4wd overheat, im just saying they run hotter engine temps most of the time compared to 2wd pavement princesses

 

Use whatever you want. I use synthetic in the crawl box and tcase since that unit tends to get hot, Marlin recomends it, and it always comes out clean when i change it evrey 6months. I run synthetic in the engine, that comes out clean evrey 8k when i change the oil.

As for redline mt-90, I ran that in my trans and noticed no difference what so ever over the unknown mystery lube that it replaced.

 

Ok, I agree with most of this. I just took your initial post to mean that in 2WD on pavement you'd be running hotter, but I see what you're saying now. Still, my 4WD is primarily "better to have it and not need it" and a very occasional trip to the mud. Usually it's just a DD being driven ~10-20 miles a day with a nice highway/city mix.

 

and that is the best reason and logic in using synthetics, to have it "just in case" you need it.

here is a good example, lets say your radiator hose starts leaking and your running low on coolant but are in the middle of nowhere and "have to" drive out, you going to be able to drive a lot longer without doing damage to your engine then if you had dino oil.

and as I have mentioned many times the extra cost is a myth because you double the mileage life from synthetics so you cut in half the number of oil changes you need.

what those guys were referring to in the video is a lot of people put in synthetics and want to just make assumptions of how far it can go. in truth it does double the mileage you normally change your oil but that's the key. not everyone can go 5k on dino oil because of the way they drive so some people can wait 5k for an oil change while others need one at 3k or 2500 miles so its not the number you should get hung up on but determine your own mileage limit on your oil based on your own driving habits and then if you want to use synthetics you double "that" number and not just go by the 10-12k mileage life recommendation that works fine for the "average" vehicle.

 

I can agree with this based on engine oil, but since this thread is about gear oil high end synthetic gear oil like MT90 is 3-4 times more expensive than base brand dino (witch is usually made by mobil or penzoil ect.). Even mobil one is twice the price and nowhere does the oil or your truck manual say you can go 60K on your dif oil or say the word synthetic anywhere. Run synthetic gear oil if it makes you feel good, if you brawl hard or if you just like to spend extra money but as long as you change it per the manual (every 30K, since there are no filters this is a must) you will save money with dino, period.

 

Use whatever you want to use...but I use conventional gear oils, buy them by API spec in the five gallon bucket, change them on schedule, and have NEVER had a problem. OK, the shifter bushing on my 94 toy pickup wore out after 12 years of dallas traffic.

But trust the API...

 

On more situation to add to the mix: If you frequently off rooas in mud and water you probably will cet some water into the differential(s). When you discover this you need to drain and refill ASAP. If you know you will be doing this twice a year why run high dollar gear oil only to swap it out every few thousand miles?

Theo other caveat is how close to the limit are you pushing that transmission (or transfer case or differential)? If you have motor swapped to a 400 lb/Ft LS3 V8 then you probably are running the driveline harder that stock was ever designed. In this case upgrading to synthetic fluids should prolong the life of that driveline and SAVE you money. (and go easy on those front axles).

Personally I justify synthetic because I change it less often, since I do this myself it saves ME time.

 

This. You said it much more articulately than I could have.

This also. However, the caveat to your caveat is that every "good" truck owner must have already done the breather relocation mod, precluding the remotest possibility of water ever entering the differential, right?

Any takers on the other half of my fire tinder? The evils of GL-5 on a transmission specified to receive GL-5?

 

This.

 

Same, here. In all good concious I couldn't drive, parked her until the keyboard mechanics here nail it all out in a fiery battle that'll surly leave keyboards and screens covered in a layer of partially chewed doritos and Mt. Dew spray. I'll come back once this particular horse has been beaten to a viscous pulp strewn fluid.

I kid of course. Synth still seems overkill for anything besides the tranny and engine.

 

These days almost all gear oils are GL-5, which is fine for any manual gear box that calls for GL-4 or GL-3. just don't go down in numbers

 

Hard to say. Toyota had always specified GL5 in manual transmissions in 1st gen and 2nd gen Tacos... until 2015. I can think of three possible reasons:

1. Something changed in transmission design between 2014 and 2015.
2. Toyota found through the last decade of service experience that GL5 results in faster wear.
3. Toyota marketing came up with a new magical "Toyota genuine shifter oil". By disallowing GL5, they subtly push more people to buy the Toyota fluid at greater cost.

 

Interesting. Wasn't aware of this change.

 

And the winner is...synthetic!

Last minute change of heart. My local Advanced doesn't carry the cheaposaurus in

$30 75W-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75W-90. I could have driven across town, but now they offer a store brand synthetic for only $9 a qt...so I could part with $16 in the name of laziness and synthetic.

On an unrelated note, I started spraying all the drain/fill plugs down with acetone:ATF today (except the front diffy fill plug, can't get to it). We'll see how well that miracle elixir works come Saturday. It looks like the previous owner already buggered the tranny fill plug a bit so I'm kinda nervous.

 

Dino oil vs. synthetic oil is really about preference. I noticed my engine runs smoother with synthetic oil and it also allows me to go longer between oil changes which is nice.