| Author | Message | ||
| John Rigby (24.174.234.92)
Rating: N/A |
Last year after reading lots of posts and an endosment by fast fred recomending syinthetic in my 4104 gearbox I changed over.I used Royal Purple and it has never changed gears easier,its like having a new gearbox. Last night I attended a show which included a booth by Royal Purple,the chief engineer said if I like the feel of the gearbox I would love the performance if I also changed the engine oil to R.P. He recomended 15w40.saying that initially when cold the 15 will reach and lube better ,and as the heat builts up the viscosity would change and at 175deg i would be running on a grove of 40w oil. He said the only consideration is how long ago was the engine rebuilt.It was 75k which was not a problem. Is anyone out there running synthetic in the engine? Also has anyone any input on this subject? The engineer said longer life, better fuel milage and more HP. Thanks John | ||
| Nelson 4104 Knoxville (64.12.96.235) Rating: N/A |
Just a quick question on problems with leaks useing synthetic in the 4104 transmission? Past posts indicate this could be a problem. Thanks Nelson | ||
| John Rigby (24.174.234.92)
Rating: N/A |
Nelson The feel of the much improved shifting far overcame any additional minute leak I had if any,when I changed over.I also think when you change and expect to find more leaks you look harder and even if they had been there to begin with,you blame the oil. John | ||
| RJ Long (24.127.74.29) Rating: N/A |
John - The issue of multi-weight and synthetic oil in the two-stroke Detroit has been hashed over numerous times on this board and others. The definitive answer is found here (print it out, it's 32 pages long): http://www.detroitdiesel.com/public/svc/lof/7se270-9912.pdf Summarized: Do NOT use multi-weight oil. Do use straight 40 wt CF-2 oil with less than 1% ash content. IF your Royal Purple chief engineer can come up with synthetic 40 wt CF-2 that meet's Detroit's specs, it might be ok. But I've never seen any synthetics in single-weight formulas, they've all been multi-weights, which DDA says is a No-No in your two-stroke. IMHO, stick to Chevron Delo 100, Shell Rotella or Mobile/DDA Delvac. . . RJ PD4106-2784 Fresno CA | ||
| Jeff Miller (205.217.70.77)
Rating: N/A |
To understand why non-synthetic multi-viscosity oil is not recommended in DD 2-strokes, and in my opinion not recommended in any engine, you have to understand pretty much how they're made and where the ratings come from: A straight 40weight oil does not stay the same viscosity over its temperature range, it has a natural tendence to get thick when cold and thin when warm. This natural curve is what the rating is based on. If it did not get as thin when warm or as thick when cold as a normal oil, it is not a straight weight oil but a multi-viscosity. To make a 10W-30 oil, you start with a 10weight oil, and add viscosity modifiers to produce an oil which doesn't thin as much when it gets cold, therefore its cold properties are similar to a 30weight oil. These viscosity modifiers are typically short-chain polymers, which unfortunately have very poor shear properties, and break down in high-shear applications such as camshaft followers for example. Essentially, the 10W-30 shears at a 10weight level, and only protects at these points like a 10weight oil, when the engine needs protection of a 30weight. Further, these viscosity modifiers break down permanently, and the oil thins with use. You don't want this to happen, if your engine needs 40 then it should get 40. A 10W-40 is pretty much like pouring in 10weight oil in many parts of the engine, and eventually in the entire engine. Enter synthetics. Mobil 5W-30 for example has no viscosity modifiers at all. The oil doesn't thin as much as a dinosaur oil as it warms, nor thicken like peanut butter when cold, so it does not follow the curve of a traditional dinosaur oil, therefore in testing it exibits behavior that earns it a multi-viscosity rating. With no viscosity modifiers to break down, it protects the engine even in high-shear like a 30weight oil, and for many more miles as the long-chain polymer oil is more durable. Its higher flash point and other high-temperature resistance as well as its reduced tendency to break down on cylinder walls and cause ring sticking and scoring are bonuses. We had a local trucking company, Holland Motor Express, who changed over to Mobil Delvac 1 synthetic in the early '80s and it was quite successful. Their primarily 6V92TA fleet returned better fuel mileage, lower oil consumption, and according to the mechanic that I talked to the biggest savings was in un-scheduled downtime as the synthetic oil had reduced their internal engine failures. As to leaks, in the '70s there was a formulation that didn't swell the seals as much as typical diosaur oils, so changing over after the engine had worn in swollen seals did start/increase leaks. Changing back would stop the leaks again. These oils were re-formulated about 20years ago and the leak myth is for the most part ancient history. For the most part. The other part of the leak story is oil viscosity. When an engine with dinosaur oil is shut down and gets cold, you have a hard time getting the stuff out of the drain plug, much less through the tiny leaks in the seals. Synthetic oil never gets that thick, so it leaks 24/7 through those sloppy seals and gaskets, you could see an increase in oil drips. It is up to the individual whether the additional expense is worth it, I have chosen synthetic engine oils for almost 30years now and will continue to. Some get Mobil 1, some Mobil Delvac 1, and the coach gets RedLine synthetic cause it is nothing but the best for my baby. I probably wouldn't wear out the engine's internals anyway, but that turbo on the other hand, sure does get hot, ... | ||
| Curt (67.30.217.42)
Rating: N/A |
How about an oil called "Lucas" I think. Is it safe to usein older units. Thanks, Curt | ||
| j clark (152.163.188.227) Rating: N/A |
Good post Jim! How often do you change your engine synthetic oil? I use synthetic in the diff and tranny, but unable to get past cost effectiveness of frequent engine oil changes (still using Delo 100 40wt) jc | ||
| John Feld (Deacon) (150.199.209.22)
Rating: N/A |
As an over-the-road truck driver for 40+ years I have reached the conclusion that the best oil is the one that performs well in any given engine, not all engines are the same. A 6-71 ran best on Delo 100 & hard to find Delo 200. A 8V71 would perform well on Delo 100, 200 or 400, Rotella or Rotella-T. The newer engines for the most art performed well on multi weight Rotella T. Keep in mind that any oil company is out for your business, and of course theirs is best. Your engine is not a test lab, much depends on the driver as well. Several times I drove engines that had been mis-used, lugging on the hills is a big no-no, drop a gear and keep that Detroit wound-up in the power range that breaths. After a 500 to 1,000 mile distance the engine performed better when properly operated. An engine is a big investment, treat it as such and you should never have to replace it. With the few cold starts most RVers will do I see no reason to push the manufactures recomendations. Start your engine, give it time to warm up before putting a load on it and you will have less engine problems. Just my two cents worth. BTW: we tried Mobil and lost 5 PSI oil pressure over the board on 16 of our fleet, others had no loss, go figure. To insure a constant supply of oil we always sent a case of oil with each unit, nothing worse than mixing oils on the road because we couldn't find our brand when needed. As a side note, most trucks change oil at arould 10,000 miles. We started to use oil analysis. After much trial and error here is what we ended up doing. Drop the filters at 10,000 miles, then again at 8,000 miles & 8,000 mile intervals up to 60,000 miles when we did a complet change. Oil gets contaminated, it does not wear out, that is why the "ash" factor is so important. Next time you check your oil take a little and rub it between you finger and thumb, it should be slick and not rub away easy, if it does, get that oil changed now, no matter how many miles you have on it. Another consideration is the wear on your engine. Bearings tolorance is set to include a film of oil so that metal-to-metal contact never occures. As bearnings wear they require a heavyer oil to maintain that "gap", a slicker oil to lub that metal-to-metal contact, change that oil more frequent or use additives to add body to the oil. While oil in itself is a matter of oil, it has many links to other systems, driver driveing habits, miles on engine, ambiant temperture, grade of fuel, quality of filters, idle time, etc. Two identical trucks, two identical routes of operation, two different drivers, one lasts 150,00 miles to overhaul, the other 250,000 miles, what is the difference? Belive it or not, changing to a different oil to suite the driver habits increased the overhaul time in truck one. One size does not fit all. John Feld 4104-2260 | ||
| dounan (65.96.89.171)
Rating: N/A |
this is all interesting. my? is: i just rebuilt my 6-71 in my 04, can i --- should i break it in with a synthetic? i've been told not to . does any one have any input on this. i do plan on running the engine and trans. on syn's. thanks | ||
| steve souza (Stevebnut) (24.91.241.242)
Rating: N/A |
amsoil has a straight 30 weight oil but i never tried it. It might be worth looking into! as far as multi grade oils IN DETROIT TWO STROKES it is a no-no as cylinder liner wear drastically increases. Steve | ||
| John Feld (Deacon) (150.199.209.47)
Rating: N/A |
Dounan, never, never break ANY engine in with syn oil or multi grade oil. Your 6-71 is intended to use a low ash streight 40 weight oil such as Delo 100 40W. Next time you get around a truck stop take a look at what the truckers use, or ask an old truck mechanic. I cannot understand the fasination with syn oil and heavy equipment, its not your Honda Accord. John | ||
| dounan (65.96.89.171)
Rating: N/A |
thanks, john. i'll look into it. dounan | ||
| Larry (208.18.102.19) Rating: N/A |
I read your post it was very interesting. can you give me a link where to purchase "Redline synthetic " if that's what you have found to be the best? Thanks, Larry ps; tried to email you but keep getting it returned. | ||
| Mark Medin (209.79.199.153)
Rating: N/A |
Interestingly, Royal Purple DID make a synthetic that was suitable for 2-stroke Detroits, called Royal Purple 40DD. The publication I have is dated 08/01, so they may still make it, but I can't be sure. | ||
| Jeff Miller (205.217.70.77)
Rating: N/A |
Larry: www.redlineoil.com I don't know if they make a 2-stroke oil, mine is a four stroker. Expensive stuff, I think I pay about $35/gallon for the diesel oil, but it is polyolester based, pretty expensive basestock. - Jeff synrgdsl@iserv.net | ||
| FAST FRED (209.26.115.13) Rating: N/A |
For a motor home the big problem with synthetic is RUST. These oils are great in the 200,000 mile over the road truck (or in a Total electric full timers genset) , but not for sitting for months on end. The lubrication is great , some folks with (home made) Honda gen sets get 5000 hours from there gas gadgets, but I would be very leary of using synthetic in a coach engine. Tranny , fine , rear axle, great, even in the greased wheelbearings, good choice , but the coach engine does not usually get constant enough use. Might be OK for a planed trip to AK , where your going to go 12,000 miles in a few months , but I'd sure pull it on the return to ordinary RV use, sitting. FAST FRED | ||
| Jeff Miller (205.217.70.77)
Rating: N/A |
Fred: This is the primary reason that I chose Redline synthetic over my old syn. diesel oil: Mobil Delvac 1. The RedLine diesel oil TBN is 14. The TBN or Total Base Number tells how much reserve alkalinity the oil has, which will buffer the pH and keep it from getting too low (corrosive). Many other oils didn't have enough reserve alkalinity (high enough TBN) to be considered an "extended drain oil". A synthetic in general has no more tendency to allow rust than any traditional oil, in fact the abililty to stay thicker at high temperatures leaves the oil hanging on hot surfaces after shut-down and protecting them much better than the over-thinned hot dinosaur oil. This combined with a high TBN will protect at least as well as a premium non-synthetic. | ||
| John Rigby (63.185.81.172)
Rating: N/A |
I very much appreiciate the feedback, and with your input I was able to talk more with Royal Purple. There RP ASE 40 having an API SPEC OF CF,CF-2/SJ. is a staight 40 weight oil and meets all D.D. specifications for 71 series engines. I was told this oil will clean all areas of the engine,especial the rings, where deposits of soot and carbon have formed ,that don,t allow the rings to move and do their job.Keeping the combustion oil and gases out of the crank case and the oil in the crank case. A refrence was gived of a company having 12 tug boats working the Houston area ship channel,both the 12 tugs engines and pumps were powerd with either 671 or 871,s.using RP The cost of repairs to Stewart and Stevenson were cut in half emmediately.they used less fuel and oil,also developed more H.P. As you can no dought tell I am very close to a change.Thanks John | ||
| FAST FRED (209.26.115.212) Rating: N/A |
"A synthetic in general has no more tendency to allow rust than any traditional oil, " If this were true Synthetics would have much more acceptance, unfortunatly its FALSE. Go on some of the avation sites ,(piston engines) you will see the synthetic rust problem discussed for years. The synthetic fluid drains very well , leaving a very clean surface that begins to rust almost immediatly Esp in a DD that is open to breezes blowing thru the engine, bringing fresh moisture with every change in temp/ humidity. Leave it for the gear box , unless you really drive miles like a road truck. FAST FRED | ||
| Jeff Miller (205.217.70.77)
Rating: N/A |
I know that it has some unique problems associated with piston aviation engines, and is not recommended for them, but never heard the rust issue. Learn something every day. I guess that you need to make sure that it is at least as tanacious as hot dino oil? This is a property that varies between formulations, is any particular syn. oil better or worse than another? | ||
| FAST FRED (209.26.115.226) Rating: N/A |
From what I can learn ALL synthetics have same properties, just different markups. In trannies the synthetic DOES seem to leak more , however some are quite compatable with std oil and a quart or two will give the low cool viscosity that makes shifting a pleasure, and still have the great sheer qualities that reduce the wear. FAST FRED | ||
| Jeff Miller (205.217.70.77)
Rating: N/A |
I do know that there are vast differences between the syn. oils, their basestocks, and their additive packages. The Mobil and Amsoil for example (and most synthetics) are not made with the polyolester basestock of the Redline and I believe the Royal Purple. For example, some of the oils (ex: Mobil 1) swells seals less than does dino oil. This was a problem in early synthetics, so Mobil re-formulated in the mid-70s to provide an oil that swells the seals similar to a dino oil. This early formulation was what lead to the myth that synthetic oils will actually cause leaks. It is well known among vintage car circles however that this still can occur if you put many syn. oils into an engine that has worn the seals in with dino oil, but switching back to dino oil or a part-synthetic swells the seals and the leak again stops. We've learned that bad leakers have to be switched back to dino oil (this was actually explained in a technical bulletin published in the Mercedes-Benz Club of America's monthly mag regarding syn. oil leaks in vintage Mercedes, I believe feb. of '00). Other oil basestocks such as the polyolester of RedLine actually cause the seals to swell slightly more than a dino oil. Although this is currently my oil of choice for my coach, I do have some concern that I eventually will not be able to switch to an oil with properties which will swell the seals less, they will have taken a set and worn into their new size. I haven't seen this yet in practice, but then in 30years I've never seen a need to switch an engine from synthetic to dino oil, even though I've switched many engines to synthetic. I'll try to find a reputable URL with this information all properly explained and verifiable if you're interested, there is really a lot of research and information in the syn. oil industry. I'll probably make some more good contacts at the SAE conference next month, I'm looking forward to that also, and will pick up any technical publications on lubricants, one of my favorite subjects there. BTW, I didn't know you are a pilot, what do you fly? I had never looked into it as I never fly on piston aircraft, but I had been told by my pilot relatives that syn. oil (although exclusively used in aircraft turbine engines) had a problem with aerosolizing at high altitudes, never a rust issue. This is new news to me and I'd like to find a verifiable source on this rust issue to forward to them if you can find one for me. If you want to send me an email I can reply to it and include some great references and comparisons of oils and properties that I have in e-mailable format. - Jeff | ||
| RJ Long (24.127.74.29) Rating: N/A |
I sent the following message directly to RedLine's tech support link off their website, and got a response from a Dave Grandquist that everyone might find interesting: Does Redline formulate a synthetic oil that meets Detroit Diesel's specifications for their two-stroke diesels? This would be for their Series 53, 71 and 92 engines. They basically require a straight 40wt CF-2 oil with less than 1% ash content. Here is a link to their published specifications for these motors: http://www.detroitdiesel.com/public/svc/lof/7se270-9912.pdf I would appreciate a response, as I am contemplating synthetic oil for my 8V71T Detroit engine in my coach. I am currently using synthetic in my manual transmission and rear axle, and am quite happy with the results. If Redline does formulate an oil that meets Detroit's specs, can you direct me to a local supplier? Thank you, RJ Long Fresno CA Sorry Red Line doesn't make a low ash diesel product for the Detroit two stroke. Regards, Dave Red Line Oil | ||
| Jeff Miller (205.217.70.77)
Rating: N/A |
I guess that leaves only us four-strokers. | ||
| Gary Carter (68.27.250.38) Rating: N/A |
DD recently added a straight 40 weight synthetic oil their approved list of oils and in fact sell it themselves. Understand it is a Mobil product also available from Mobil. | ||
| DaveD (216.18.113.69)
Rating: N/A |
Anything I've read on the subject seems to suggest that the molecular structure of synthetic oils tends to make them more prone to leakage past seals than mineral oils. This has been observed mainly when the oil in used engines was switched to synthetic. However this may have been addressed to some extent by the addition of compounds which cause the seals to swell somewhat. In an engine with new seals, this should be less of a concern. DaveD | ||
| John Rigby (63.185.81.246)
Rating: N/A |
On checking a little futher we find Penske Is on the board of DD and on the board of Mobil.No wonder other oils are having a hard time wth DD approvals....... John | ||
| TVP (63.122.65.97) Rating: N/A |
more food for though .. from a die hard racer !! don't forget about the the separation problems .. i.e. synth oils DO NOT mix with gas or diesel !! so as these fuels slip by the rings and enter the crank case .. they WILL NOT mix with your synth oil .. and end up separating from each other . they entering the oil pump in sections so you end up running oil for a second then fuel , then oil ... and as we ALL know .. diesel doesn't do a good job as a lube  here's something the tree huggers will love .. what are you going to do with your OLD syth oil ?? probably recycle it WITH your dino oil ??? you know there is NO way to recycle syth oils !!!! it doubles the expense in recovery as alot of recycling is actually burning the oil .. you can't burn a synth oil ... TVP | ||
| Jeff Miller (205.217.70.77)
Rating: N/A |
TVP, I'd like to know your source for the "synth oils do not mix with gasoline and diesel" claim, they've always mixed for me. Also, why can't you burn synthetic oil? It is after all based on crude oil, and does burn, and my recycling dropoff tells me that it recycles just like any other oil. ??? Just like to see some resources for the info. | ||
| Chuck Harris - PD4104 (207.172.11.147) Rating: N/A |
TVP, That is just plain wrong! Stop spreading garbage. -Chuck | ||
| Stephen Fessenden (Sffess) (65.130.9.6)
Rating: N/A |
An auto mechanic was explaining to me that in modern car engines the moving parts are designed to hydroplane on the oil film. Yep thats what he said GM had taught them at a special class. And therefore, modern gasoline automotive engines need very light oil for maximum efficiency. Now I can't imagine the bearings in a DD hydroplaning so we probably cannot easily take recent automotive experience and try to apply it to large diesels. I agree with Fast Fred on wanting an oil that thickens up and stays put when parked for a month or so. Synthetics won't do that. The problems I have heard about with synthetics were in airplanes and cars like corvettes both of which may not be used often enough. | ||
| Skorpio (Skorpio) (24.92.193.195)
Rating: N/A |
All sleeve bearings "hydroplane", this is how a sleeve bearing works. If it wasn't you wouldn't have a need for oil pressure or for that matter oil. If a Detroit didn't work this way it would just have grease fittings on the journals (although this still hydroplanes on lubricant). Frankly the only thing I can see detrimental to the synthetic oil cause is economic practicality. From what I understand Detroits almost universally leak and burn oil, so it just may not make economic sense. If it leaks and burns, a synthetic will probably leak and burn faster and cost a hell of a lot more with minimal return. Synthetics varnish less, and gunk less, it seems Fred is eluding to the fact that these are undesirable qualities in a often idle Detroit. The idea that synthetics are too thin to cling to hot parts seems incorrect, one of the major advantages to synthetics is the fact that they embed themselves into the porosity of the metal structure better than fossil oils. Synthetics are also specifically more resistant to fuel breakdown. I run synthetics where practical, but I don't know that I would in a Detroit, simply because if adding oil to the crankcase is necessary to its service station maintenance, synthetic is just not cost effective. If you are constantly turning over the oil in the standard operation of the engine then the longevity of the product is probably greatly diminished. A lot of older engine designs, I could see having problems with synthetics if they were built the way they were originally built. Cork gaskets and rope seals and synthetics are probably not as good a combination as the more modern trend towards silicone seals and glue together gaskets which don't rely on the engines goop to keep things sealed up as the product degrades over time. I've seen gasoline engines converted to run on propane that have run synthetics, and between the clean highly detergent fuel that propane is (almost no lubrication properties at all and also hardly any carbon buildup) and the bonding properties of the synthetic lubricant, these engines look like fresh crate engines after 100,000 miles inside. You have a hard time even reading the level on the dipstick. My father was a mechanic that worked on the NICOR fleet, 1000 cars and light trucks running propane. They would sell them off when the bodies rusted out, engines always ran great (sold de-converted back to gas) and all had well over 100,000 miles on them. Seals were all like new, cylinders all still had factory honing marks, inside of valve covers looked like it was just purchased. Full fluid changes and points once a year, maintenance was not based on hours or miles, but anniversary. Most of these cars were for meter readers and they drove them like they hated them. I swear there was a NICOR Suburban in every driveway in the town I grew up in, all rust buckets and all ran great. BTW this was years ago and the original Mobil 1 is what they were using. The vehicles ran propane with gasoline for cold weather starting (This Was Northern Illinois). They ran factory oil until the first manufacture recommended oil change, then switched to the annual schedule. On average they ran probably 95% of the time on propane and averaged 25-30,000 stop and go miles a year. |