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Synthetic or Not?

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If I put synthetic oil in like Amsoil, is it going to help reduce some Engine and Trans heat while towing up grades?

I've heard that's an inherent issue especially with the 68RFE Trans.
 
Your engine wont run any cooler per say. If following OEM service intervals its hard to argue against regular dino oil. Where synthetic really shines IMO is operating in extreme temps hot and cold, and is why I personally use synthetic (plus I run extended intervals).

As far as ATF all ATF+4 is synthetic. If it is a licensed ATF+4 fluid there is little difference in brands.
 
In theory, it should reduce heat, but will it be noticeable? no.

Based on my own experience, and reading here and elsewhere, I have yet to conclude that there is any heat related issue with the 68RFE (at least with the current generation of cooling). FYI, ATF+4 that comes in your trans is synthetic.

Are you currently having a problem or are searching for a solution for a non-existent problem?
 
I use synthetic because I've read that synthetic oils are better at preventing deposits in the turbo charger on shut down.
 
I've not encountered any 68RFE heat issues when towing our 19K GVWR 5th wheel up grades - as long as the torque converter remains locked. If you get into some tight, 1st & 2nd gear grades with switchbacks where the torque converter is unlocked, that's another issue. In the latter conditions, I've seen 220 degF to 225 degF on the EVIC as opposed to the normal 160 degF to 180 degF. I don't know that the specific brand of ATF is going to make much difference in dissipating heat generated by fluid shear in the torque converter.

This past summer we were towing up into the Davis Mountains in west Texas with 2 other couples, one driving a Ford F450 and the other a Chevy 2500 Duramax/Allison. Ambient temperature was around 95 degF as we started the 35 mile climb. We were conversing over the CBs as we went into the mountains because the driver of the Chevy was concerned as he was seeing 210 degF transmission temperatures and rising. The driver of the Ford reported about 205 degF - my EVIC was reading 178 degF. :)

Rusty
 
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I use synthetic because I've read that synthetic oils are better at preventing deposits in the turbo charger on shut down.

I am under the impression that some of the synthetics recommended for extended oil change (AMSOIL for example is what I use) have better additive packages. And that they have better high heat stability.

So I support the above assertion that they are better at preventing deposits that could reduce oil flow between tight tolerances.

I also had a personal experience where I believe someone sabotaged a previous SUV of mine by loosening the lower radiator hose and draining coolant out of my radiator while I was sleeping.

I was an adjunct instructor at a local university and the night before the day of my final exams, I believe some students drained my radiator of coolant so I would not be able to give my final exam. I felt like I was being followed the week before the finals. You know...... that feeling you get when you know something is suspiscious?????

I didn't discover it until I saw my temps increasing on my vehicle. The AMSOIL got burnt, but was still protecting my engine even though it was mildly burnt.
The vehicle lasted me another 40,000 miles and was still running when I traded it in. But If I had had conventional oil, I'm sure the engine would have been toast when it overheated.

I will continue to use AMSOIL in all my vehicles because I believe it is a high quality product.
 
"Synthetic" is a marketing term abused by major oil companies. Make sure you know what you are really getting. https://en.wikipedia.org/wiki/Synthetic_oil

Friend has a V6 Dakota out in hot AZ that regularly, 2-3 times a week, tows a trailer loaded past the limits to the scrap metal yard for The Boy Scout Troop. It has AMSOIL in the auto trans since about 10K miles and wasn't changed since. It now has over 1/4 million miles on it. I wouldn't recommend this myself, but, it is what's been done.
 
In theory, it should reduce heat, but will it be noticeable? no.

Based on my own experience, and reading here and elsewhere, I have yet to conclude that there is any heat related issue with the 68RFE (at least with the current generation of cooling). FYI, ATF+4 that comes in your trans is synthetic.

Are you currently having a problem or are searching for a solution for a non-existent problem?

When I first talked about buying my truck, there were many proponents for the Aisin Trans who spoke of the 68RFE heating up too much and that the Aisin was the only way to go.

I've towed my 15,000 lb Cardinal through the mountains and have not seen any significant rise in temperature except for bringing the RV up to where I live. I'm on the side of a hill with a fair grade change with several switch backs and the highest I've noted in Trans temperature was 195*F. Although, the outside air temp wasn't anywhere near hot so it may make a difference come summer here when temps hit 95*.

My enquiry was purely as a result of what I was told about the 68RFE and wondered if Synthetic oil made a difference in Trans. running temp. Trying to be proactive if I needed to be.

Oh, and I didn't know the Trans came with Synthetic. Duh! Haven't gotten that far in my manual yet.
 
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I'd run synthetic in the engine if there wasn't the warranty requirement to change the oil every 6 months, regardless of mileage. That is about 5000 miles for me. Regular oil works perfectly fine. If I cannot get the extended drain interval (15,000 miles) from the synthetic then it isn't worth it.

I'd run synthetic if I was operating in cold temperatures, like below zero F. But I'm not.
 
I'd run synthetic in the engine if there wasn't the warranty requirement to change the oil every 6 months, regardless of mileage. That is about 5000 miles for me. Regular oil works perfectly fine. If I cannot get the extended drain interval (15,000 miles) from the synthetic then it isn't worth it.

I'd run synthetic if I was operating in cold temperatures, like below zero F. But I'm not.
I can respect your viewpoint, but look at it another way :
Near home, 5W40 Rotella T-6 Synthetic is $19.57/gal. 15W40 Rotella is $12.97/gal. That's $6.60/gal more.....or an additional $19.80 per oil change.
 
I'd run synthetic in the engine if there wasn't the warranty requirement to change the oil every 6 months, regardless of mileage. That is about 5000 miles for me. Regular oil works perfectly fine. If I cannot get the extended drain interval (15,000 miles) from the synthetic then it isn't worth it.

I'd run synthetic if I was operating in cold temperatures, like below zero F. But I'm not.

I drive about the same miles per year as you. But because of my city driving and many cold starts, I pay the extra $40-$50 or so per year for synthetic.
I know my synthetic protects better. I'd like to go to 20 w50 synthetic, because I suspect my city driving causes mild fuel dilution of the engine oil.

But I don't see any 20w 50 without the metallic friction-reducers that screw up the catalysts in the exhaust system.
 
I can respect your viewpoint, but look at it another way :
Near home, 5W40 Rotella T-6 Synthetic is $19.57/gal. 15W40 Rotella is $12.97/gal. That's $6.60/gal more.....or an additional $19.80 per oil change.

Agreed, T6 is surprisingly cheap. There are many reasons to run synthetic, not just for a longer drain interval.
 
What about it? If you mean to extend it, I don't know why you'd want to. About $15 twice a year is not a big deal.
 
Although high quality synthetics have a good detergent package, these synthetic oil companies say change the filter even if you extend the oil change.
Nobody recommends extending the filter. You might end up running a clogged filter (or partially clogged)
 
The Donaldson DBL 7349 (formerly ELF7349) is a 15k mile oil filter. I believe Amsoil markets it at 25k miles, but UOA would be required to safely acheive that mark.
 
What might have been a "15K oil filter" for my 2002 almost certainly wouldn't be on my 2011 - a non-SCR engine that uses LOTS of EGR and makes LOTS of soot. Would I try it? Only if I had an oil filter differential pressure gauge like the large industrial engines my company manufactures. Unfortunately, that critical bit of information isn't available on our trucks.

Rusty
 
Was looking at some reviews for diesel approved oils. I find it weird that Rotella T is rated higher than Rotella T6 because it has higher load carrying capacity. I have been using exclusively amsoil for years. But my local auto parts store has Rotella T6 on sale, so might give that a try. I think that the non synthetic version has higher load carrying because it doesn't flow as well. I will stick with the synthetic.
 
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