Is 10w-30 dino enough protection in very hot envir

[Adamwest]

Of the several cars in my family, I drove my 1988 Tercel with an automatic transmission about 110 miles per day round trip this past summer for my commute. This was in the desert where temperatures routinely exceeded 115 and 120 was not uncommon. I really pushed the car hard with the AC on with the temp needle frequently getting close to the red zone on hills. On highway 40 the speed limit is 75 mph in places with actual speeds closer to 80. Lacking a tachometer, I don’t know how high the car revved, but it really wailed away. Currently the car has a little over 102k miles on it.

I would have used synthetic oil, but it has a slow but present leak from the timing belt seal that I need to get fixed. It is my understanding that until I do that, it would leak more due to the thinner nature of synthetic. I didn’t run 10w-40 since I have heard that it is not good to use it due to the amount of VII present in such a large numeric difference.

My question is, in this well running engine, should the 10w-30 have provided fine protection, or is something heavier needed for these conditions? My Tundra didn’t seem to have any trouble in these conditions, but the Tercel felt really pushed. I have also been advised by autoparts’ employees against synthetic on this older car, but I don’t know if I trust their advice on that. Thank you for your input.

 

[kingrob]

Why are you afraid of the Gp VII in 10w40? On an 88 Tercel, I'd run any decent 10w40 conventional for 5k mile OCI's if you're putting 110 miles a day on it. Heck, I'll take it a step further and recommend 20w50.

 

[Adamwest]

I had just read in a few places that 10w-40 oils were not a good idea. I was thinking actually about running 15w-40 Rotella at one point, but I'll think about that for next summer. The winters are much cooler out here. I was just wondering if in those circustances the 10w-30 would have been enough.
As an aside, the oil looks pretty black and nasty way before the 5k miles so I've been changing it at 3k.

 

[BrianWC]

Your Tercel felt "pushed" compared to your Tundra because, well, there's a big difference between a Tercel and and Tundra. It's going to be pushed even more if you give it a thicker oil to have to work with.

If it's spec'd for 10W30, run 10W30, nothing will blow up. If you want to run synth, run synth. Synths aren't thinner. They have to meet the same viscosity standards as their dino counterparts to be classified at the weights they are. Alternatively, try a high mileage oil like Valvoline Maxlife. Also, oil color is no true indicator of oil life.

 

[rg200amp]

Originally Posted By: BrianWC
Your Tercel felt "pushed" compared to your Tundra because, well, there's a big difference between a Tercel and and Tundra. It's going to be pushed even more if you give it a thicker oil to have to work with.

If it's spec'd for 10W30, run 10W30, nothing will blow up. If you want to run synth, run synth. Synths aren't thinner. They have to meet the same viscosity standards as their dino counterparts to be classified at the weights they are. Alternatively, try a high mileage oil like Valvoline Maxlife. Also, oil color is no true indicator of oil life.



I agree 100%

 

[Quest]

Originally Posted By: BrianWC
Your Tercel felt "pushed" compared to your Tundra because, well, there's a big difference between a Tercel and and Tundra. It's going to be pushed even more if you give it a thicker oil to have to work with.

If it's spec'd for 10W30, run 10W30, nothing will blow up. If you want to run synth, run synth. Synths aren't thinner. They have to meet the same viscosity standards as their dino counterparts to be classified at the weights they are. Alternatively, try a high mileage oil like Valvoline Maxlife. Also, oil color is no true indicator of oil life.


+1 to that.

 

[Adamwest]

Thank you for the input. I thought it was fine but started to second guess myself after thinking about it too much! I also have a 1988 Volvo 240 with 210k+ miles that I run 10w-30 synthetic in that seems to be doing well.

Of course the Tundra is a much more capable vehicle which is why I wasn't too concerened about it. It is our tow vehicle and my wife commutes in it 130 miles per day with no issues.

I guess that when I hear people talking about making changes to accomodate hot weather-maybe high 90s or something, I can't help but to wonder what impact the brutal Mohave Desert would have.

 

[BrianWC]

You should be fine. But if you've got a leak, maybe try Maxlife 10W30 or 5W30 or even Auto-RX.

 

[Adamwest]

Good idea, I'll give it a try. Right now I've got Mobil Clean High Mileage that I have topped off with a little Castrol GTX. I've been looking at the ARX posts to familiarize myself with it. None of my other engines get the oil so dirty, but I didn't get this car until it had 90k miles.

 

[JDD]

+1 on the maxlife. Shell RTS would be great too. Either 5 or 15-40.

 

[Bill in Utah]

Originally Posted By: BrianWC
Your Tercel felt "pushed" compared to your Tundra because, well, there's a big difference between a Tercel and and Tundra. It's going to be pushed even more if you give it a thicker oil to have to work with.

If it's spec'd for 10W30, run 10W30, nothing will blow up. If you want to run synth, run synth. Synths aren't thinner. They have to meet the same viscosity standards as their dino counterparts to be classified at the weights they are. Alternatively, try a high mileage oil like Valvoline Maxlife. Also, oil color is no true indicator of oil life.

+3

This screams STICKY!

Welcome to our new member.

 

[dkcase]

I'd consider an auxiliary transmission cooler, if I were working it that hard and watching my temp gauge.

If I wanted a new oil I'd go to Shell Rotella T Synthetic that someone mentioned above, 5w40.

 

[Baddog]

... with an automatic transmission ... with the temp needle frequently getting close to the red zone on hills.

You want to get the cooling system checked also. Putting synthetic trans fluid in would not be a bad idea since it is cooled by the radiator.

 

[Adamwest]

Thank you for the welcome and all of the input. I hadn't thought about the trans fluid. I'll put that on the list. I did flush the radiator and it seems to be working to spec-I suspect it's probably struggling because the engine is turning at least 4000rpm much of the time and with the AC it is just a bit much. Now that's it's cooler I don't have to worry about it until Spring.

 

[BrianWC]

Originally Posted By: Bill in Utah
Originally Posted By: BrianWC
Your Tercel felt "pushed" compared to your Tundra because, well, there's a big difference between a Tercel and and Tundra. It's going to be pushed even more if you give it a thicker oil to have to work with.

If it's spec'd for 10W30, run 10W30, nothing will blow up. If you want to run synth, run synth. Synths aren't thinner. They have to meet the same viscosity standards as their dino counterparts to be classified at the weights they are. Alternatively, try a high mileage oil like Valvoline Maxlife. Also, oil color is no true indicator of oil life.

+3

This screams STICKY!

Welcome to our new member.

All this praise! My, my...

 

[mechtech2]

Get the crank seal fixed and get a timing belt. The oil is not good for the belt. New pulleys are wise. Pulleys can cause a belt to go bad, not the other way around.
5-40 full synthetic Rotella would be good, maybe the 15-40 also if the winter is not too cold.
Your car sees high heat and tough conditions, and a 40 is not too thick during those conditions at all.

 

[addyguy]

Those Tercel 1.5's, as with many Toyota engines, are absolutely bulletproof. You could put vegetable oil in it, run it at 4000 all day, and it would still go 400k miles...

Seriously, if it were me, I'd run 10W-30 Maxlife at 5k miles, and call it a day. Car will run as long as you want it to.

A little O/T, but: My dad had a 1989 Tercel 1.5 4-speed, similar to yours. He left one morning to go to a meeting and do some 'running around' in the city we lived in. I came home from school at about 4pm; and found the car's drainplug, and the contents on the pan, all over our driveway.

He got home at about 5pm, and I showed him what I had found. He had had an oil change the day before at the dealership we bought the car from. He said that the oil light 'had flickered' a couple of time, but not stayed on during the day. He'd driven it about 30-40 miles in the course of the day.

Had the car towed to the dealer, they 'apologized', filled the car up, and sent my dad on his way. Said they would note what had happened, but would not do anything else until the engine quit, as it was running fine at that point.

Car ran for like another 4 years, but it used a lot of oil. Point of the story is that it STILL RAN!

 

[TallPaul]

The critical factor in protection is the HTHS viscosity. As a rule thicker oil has a higher HTHS. Two 10w30s could have different HTHS if one has a thicker base oil its HTHS will be higher. Redline Oil is very good in HTHS, with 10w30 having HTHS of typical 10w40. You'll get a great HTHS if you run straight 30 weight.

 

[Steve S]

It really depends upon the oil temperatureand oil pressure.

 

[Gary in Sandy Eggo]

Originally Posted By: Adamwest
110 miles per day round trip this past summer for my commute. This was in the desert where temperatures routinely exceeded 115 and 120 was not uncommon. I really pushed the car hard with the AC on with the temp needle frequently getting close to the red zone on hills. . . . I didn’t run 10w-40 since I have heard that it is not good to use it due to the amount of VII present in such a large numeric difference.. . . My question is, in this well running engine, should the 10w-30 have provided fine protection, or is something heavier needed for these conditions?


55 miles one-way is a nice trip for an engine. 115-120 degrees is very hot, particularly when running your AC.

Frankly, under these conditions (the hot season), with speeds and temperatures that you cite day-after-day, I'd be running a monograde SAE-40 oil. If daytime temperatures were routinely 90-100F, I'd be using SAE-30 monograde. Monograde's going to put more oil between the moving parts at those high operating temperatures, and it's not going to shear down.