Synthetic oil

[montaillou]

I'm gonna try synthetic oil.

Yes, I've heard it will cause leaks. I've also read that synthetic oil cleans so it might expose leaks I didn't know I had, and I'd rather find those now, than when I'm 1k miles from home or above the arctic circle. Will it damage my seals & gaskets? Maybe, and if it does, I'll replace those with modern materials. I've also read that there were some issues with synthetic when it first came out, but those have been dealt with and after all, it's used in practically every modern car now.

My plans for this truck include trips involving hours of highway driving, lots of hours with this truck at high temps. I believe synthetic will be better for the engine under those conditions. I'm gonna experiment with day trips close to home and see how it goes.

Spoke to my mechanic that works on commercial trucks, he doesn't think it'll be a problem, except what I've mentioned. I'll be going with Shell's synthetic for diesel engines unless someone else has some recommendations?

 

[JD4044M]

I use it in everything including my Mower. Things from 1948 up to 2005 so far and love it. Dropped my 48 Power Wagons Water Temp about 15 degs back into normal range! Good stuff if it leaked before it will still leak. I have never saw new leaks using it so far over the last 15+ years. Just put it in my New to me Free 16 year old Lawn Mower and it runs nice! Bet I kill this one in less then 4 years mowing the fence lines. I do have a Brush Hog for my Tractor.

 

[Elijah95]

As with any change in oil, there’s a minor risk associated. I’ll say this though, if you end up considering synthetic for your transmission I’d steer clear until you’ve done research and read of people losing theirs in the M35A2s because of it then it’s an informed decision.

I’ve ran synthetic in my multifuel when I scored it up cheap, and didn’t notice any difference in oil leaks or consumption but YMMV. I’m with the post above, I run synthetic in nearly everything I own, and ironically I run Rotella T6 in my lawnmower.

“I put that **** in EVERYTHING!”


Sent from my iPhone using Tapatalk

 

[pmramsey]

Your truck's turbo will love it.

 

[G744]

I use it in our vintage Benz Diesel cars with the 5-cyl turbo motors. Typically, the timing chain will need to be replaced when the stretch amounts to some 6 degrees, usually at the 100K marks.

With syn oil, no stretch in some 300,000 miles, saving me a lot of work.

In the 5-ton, I run syn blend in the Mack ENDT and it runs a bit smoother.

DG

 

[pmramsey]

The ENDT powered trucks are already the smoothest running military engines ever. Running the syn-blend must drop it into stealth mode.

 

[G744]

The ENDT powered trucks are already the smoothest running military engines ever. Running the syn-blend must drop it into stealth mode.

Ha! There isn't much 'stealth' with the old girl, but as they say, 'any port in a storm'.

DG

 

[pmramsey]

Ha! There isn't much 'stealth' with the old girl, but as they say, 'any port in a storm'.

DG

Here is my 1965 M54A1 with its 1975 rebuild. It has the last version of the three military ENDT engines built for these 5-ton trucks. I admire the simple, efficient, beauty of these old Macks. Even on a bad day, I can walk past this critter and it always makes me smile. Hopefully, after six years, this is the year to lay down the U.S. Marine Corps Old Forest Green Semi-gloss.

 

[G744]

Mine is a '67 Kaiser Jeep Corp, went to Nam when new. Rebuilt in Sagami, Japan in '75. Again in 84 in Nurnburg, only bumper #s are 1st Armored. It went to Desert Shield (B4 Storm) in a really crappy CARC paintjob it still has.

The old girl has some history, I wish she could tell me her secrets.

I'll get some pix and post them later.

DG

 

[pmramsey]

Both our machines went through a rebuild in Sagama, Japan in 1975. Which means, we both have the overdrive Spicer transmissions, final ENDT improved engines, and the M809 style steering systems. My unit was built in Reading PA, and delivered directly to Vietnam in October 1965....thus no heater. It sustained damage in late 1968 and substantially more in early 1969. It was reissued to the U.S. Army Reserve unit in Lawrence Township, NJ where it served for the next 40-years until I purchased it at auction in May 2015. It had all but rotted but it runs today because it was properly prepared for long-term storage. It took almost a month to determine if I had a runner and everyday I drove it, the engine only got stronger. I completely dismantled it cab off, gutted the interior, replaced all the gauges with new ones except for the speedometer and tack...900 hours and 26,000 miles. New top, seats, glass, frames, rubber seals, hood, side-panels, fenders, steps, new doors filled with new glass and mechanisms, new radiator, aluminum fuel tank from an M923A1, all new stainless steel wheel studs, USDOT compliant brake lines, a set of new Goodyear G177s, a new bed with drop down sides with new troop seats, and a completely new front and rear wiring harness. The only non-standard change was to tap into the air shift line, and build an air driven lockout for the auto engaging front axle feature. It makes for a far smoother ride when driving without a load on the rears.

 

[G744]

A ststeside rebuild is cool. All were out-of-country with this one.

Mine has a dropside bed, albeit it is 'rippled' from a lot of heavy loads. Prolly ammo for their 155's.

I put on dual 76 gal tanks so I could make the Big Bear rally in Cal without having to stop for fuel--900mi one way. Did the trip 3 times in that rig.

It showed 22K miles on the odometer when I bought it from DRMO back in the 90's. Now double that.

One thing I love is it will pass any 809-series 250 Cummins truck on the freeway, even with it's "210" HP.

DG

 

[pmramsey]

I am busy today so I will re-post the following one of my posts from July 2016.

This is my last contribution as to why I prefer the Mack ENDT-673 5-ton over the Cummins NHC 250.
I have a 40-mile course over which I like to run a truck through its paces. It starts at Massie’s Corner at the intersection of US 522 and US211, runs through Sperryville on 211 up and over Thornton’s Gap (2,460 ft.) down into the Shenandoah Valley and turns north on US 340 following the south fork of the Shenandoah River to Front Royal. This connects back to US 522 and goes up and over Chester Gap through Flint Hill and back to Massie’s Corner. These are all 1950s type two-lane roads with posted speed limits of 45-mph for trucks and 55 mph for autos.
The route out of Sperryville is 6 miles to Thornton’s Gap and a climb of 1,100 feet that includes three switch backs nearing the top. This is not what one would exactly call a very high elevation.
Yesterday, the afternoon temp at Thornton’s Gap was 99F with a dew point of 74F and barometric pressure of 29.90. This meant the density elevation at which an engine would have to produce its power was 5,908 feet.
As with many non-turbo engines, the NHC 250 is incapable of producing more than 75% power above 5,500 feet and even that number is dependent upon proper fuel leaning which the military version of the engine does not offer. The power available yesterday going up to the gap would have been 73% of its max rated 240hp or 175.2hp. Without leaning, the estimated power output would be in the 68-70% range or 163-168hp.
On the other hand, the turbo Mack ENDT-673 maintains its full power output of 210 or 220hp (the last version of the engine installed in the 1970s rebuilds were 220) to over 10,000 feet. Yes, the Mack will run hot under these conditions as the turbo intake temperate can push 1500F under such conditions. An inner cooler and fuel leaning would have been nice additions.
The answer to the Mack vs NHC 250 is best answered with another question. Given that both trucks are very close in weight and if you are using your truck for more than recreational use, which truck would you have preferred to take over Thornton’s Gap yesterday; one with 163-168hp or one with 210-220hp?
There was a time when the Marines out of Pendleton would take an occasional convoy exercise going up to Big Bear Lake. If the weather was against them, it was not uncommon to observe an M35A2 blowing its guts out the stack and its M105 trailer slowly doing a jackknife. The Lake is 6,700 feet and density altitude can easily reach over 12,000 feet. Just hope the dry Santa Anna winds are blowing.

 

[G744]

In all her glory...

With covid, not many road trips, so it gets to work around the property, pulling the well, lifting building materials, eTc.

DG

 

[pmramsey]

Fine looking rig you have there. Do you get to use the winch much?

 

[G744]

It gets used for idiots that don't know about desert sand and caleche clay.

I usually just tow them, but if it is really muddy after a Summer monsoon, I'll stay on hardpack and winch it. I make them pull the cable out and hook it "To something that won't come off"...

DG

 

[TechnoWeenie]

There are a couple things that matter but don't matter at the same time.

The best oils available in the 60's are utter #%(& compared to even the crappiest oils today. Modern enhancements in lubricity, additive packages, detergents, surfactants, etc. mean you're already giving it something better than what they had.

Modern synthetics are great. They maintain rated viscosity throughout a wider range of temperatures, and last longer through a more robust additive package.

The biggest issue, as you pointed out, is the massive detergent package that will clean out oil deposits where you might actually want them. These aren't the newer engines with tolerances down to 1/1000th of an inch... This also means you'll probably have oil burning that slips past the rings, and increase the risk of a runaway in the event of a ring failure.

Personally, I'd try a synthetic blend, then move to a synthetic, to make sure you're not doing something so drastic as to cause a failure. Rare, and probably highly unlikely, but it's also a 60 year old truck...

Rotella T6 is my go to for synthetic, but you can find deals on other stuff, and given the age of the vehicle, I'd just get the cheapest synthetic I could find. I'd check out Tractor Supply or Walmart and see what's on sale. I've bought 5 gallon pails of 15w40 full synthetic for ~$45..

EDIT: https://www.walmart.com/ip/Synthetic-Diesel-Engine-Oil-15W40-5-Gallon-Pail-18L-4-75-GAL/543870848

 

[montaillou]

increase the risk of a runaway

I installed a air cut off. Doubles as a theft deterrent.

 

[cattlerepairman]

I installed a air cut off. Doubles as a theft deterrent.

It already comes with a "millenials theft deterrent": Standard shift transmission!

 

[montaillou]

millenials theft deterrent

Yeah, but millenials don't get drunk and say, "hey, I know how to drive that".

 

[frank8003]

oops, time to study
tribology

1. the study of friction, wear, lubrication, and the design of bearings; the science of interacting surfaces in relative motion.

oh study study............
just more