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Synthetic oils
- Thread starter Paulus
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jerrybny
Jedi Knight
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If you look thru the archives you will see this item discussed many times. TR6's are prone to small amounts of leaking so Synthetic oils being thinner by nature will leak even more. Also I've read that since the TR6 engine was designed with looser tolerances than modern cars you ar liable to burn more oil if you use Synthetic oil. I myself run Castrol 20-50w. I really haven't found any reason to switch to Synthetic oil especially considering the cost.
I run Red Line synthetic in the race engines, but they have tighter tolerances and improved sealing over the street cars.
For everyday use it's Castrol 20W50 for me, too. I don't see the need for the extended change intervals offered by the synthetics, as my street cars don't get driven that much over the course of the season. /ubbthreads/images/graemlins/frown.gif
Given those facts, it's hard to justify the extra cost.
Jeff
For everyday use it's Castrol 20W50 for me, too. I don't see the need for the extended change intervals offered by the synthetics, as my street cars don't get driven that much over the course of the season. /ubbthreads/images/graemlins/frown.gif
Given those facts, it's hard to justify the extra cost.
Jeff
trboost
Jedi Trainee
Offline
In the past I have used any quality name brand 20-50w conventional oil. While rebuilding my current motor I tightened the all the tollerances, big & small bearing clearances & added cam bearings. I also made changes & gave special attention to the problem leak areas of the motor (front sealing block, timing cover, rear end seal). This was my first solo rebuild, so I was definitly anal.
I used conventional oil until about 10,000 miles & then switched to 15-50w Mobile 1. During break-in, in the hot summer months I was able to use 10-40w reg oil & still show more than respectable oil pressure, so when it came time to experiment with synthetic I found that a 10-40w was not made by Mobile 1 . I tried their 15-50w & have been more than satisfied. So far (another 10,000 miles) no leaks & oil consumption has droped . Oil pressur readings were much more stable, especially after long highway speeds on hot days. It seems to recover better.
Now that the colder weather is coming I will try and find a lower viscosity oil. I'm not sure about the 50w in sub-freezing temps.
You certainly can't hurt anything by trying, and you only have some advantages to gain if your motor tolerates it well. I would worry more about the leaks than the motor design specs. I would doubt that a 15-50w synthetic over a 20-50w conventional oil would cause any mechanical failures.
I also use a magnetic drain plug to monitor wear & it's never been cleaner.
I used conventional oil until about 10,000 miles & then switched to 15-50w Mobile 1. During break-in, in the hot summer months I was able to use 10-40w reg oil & still show more than respectable oil pressure, so when it came time to experiment with synthetic I found that a 10-40w was not made by Mobile 1 . I tried their 15-50w & have been more than satisfied. So far (another 10,000 miles) no leaks & oil consumption has droped . Oil pressur readings were much more stable, especially after long highway speeds on hot days. It seems to recover better.
Now that the colder weather is coming I will try and find a lower viscosity oil. I'm not sure about the 50w in sub-freezing temps.
You certainly can't hurt anything by trying, and you only have some advantages to gain if your motor tolerates it well. I would worry more about the leaks than the motor design specs. I would doubt that a 15-50w synthetic over a 20-50w conventional oil would cause any mechanical failures.
I also use a magnetic drain plug to monitor wear & it's never been cleaner.
aeronca65t
Great Pumpkin
Offline
One place I've been very happy with it is in gearboxes. Nice in the Spridget and even seemed to help the Miata. I use it in the final drives too (though it's hard to measure any improvement).
Actually, though I'm pretty sure that the syn-oils are better, the oil filters are the same.
The syn-oil is probably good for 10,000 miles or more, but I'm not sure I'd like a filter to go that long.
By the way, my new van is going in for it's first oil cahnge and I noticed that the correct oil to use is 5W-20 ....I may boost that up to 5W-30 when I start towing with it.
Actually, though I'm pretty sure that the syn-oils are better, the oil filters are the same.
The syn-oil is probably good for 10,000 miles or more, but I'm not sure I'd like a filter to go that long.
By the way, my new van is going in for it's first oil cahnge and I noticed that the correct oil to use is 5W-20 ....I may boost that up to 5W-30 when I start towing with it.
aeronca65t
Great Pumpkin
Offline
No.
I'm using Castrol 20W-50.
Oil gets changed after every event (never more than 3.5 hours of engine time and usually less than half that). I don't think that syn-oils are much of an advantage with oil changes this frequent.
A very good friend of mine is a tech-engineer at Castrol.....he provided me with a bunch of tech documents indicating that Castrol was a good choice for my application.
Also, it's cheap and easy to get. I'm using Fram spin-ons for the same reason.
I did have one rod bearing failure after running them a bit longer planned (over 25 hours). In my view, that's a problem with the 1500 engine and the type of oil wouldn't make that much difference. I just put in a new crank and brought the shift light down to 5700 RPM...I'll replace the rod bearings this Winter. That should give me a better idea about internal engine wear.
I'm using Castrol 20W-50.
Oil gets changed after every event (never more than 3.5 hours of engine time and usually less than half that). I don't think that syn-oils are much of an advantage with oil changes this frequent.
A very good friend of mine is a tech-engineer at Castrol.....he provided me with a bunch of tech documents indicating that Castrol was a good choice for my application.
Also, it's cheap and easy to get. I'm using Fram spin-ons for the same reason.
I did have one rod bearing failure after running them a bit longer planned (over 25 hours). In my view, that's a problem with the 1500 engine and the type of oil wouldn't make that much difference. I just put in a new crank and brought the shift light down to 5700 RPM...I'll replace the rod bearings this Winter. That should give me a better idea about internal engine wear.
Offline
[ QUOTE ]
Castrol 20/50w with Fram filters have always been the choice for all of my cars. Just basic good quality stuff.
[/ QUOTE ]But then there are those folks who will tell you just how horrible Castrol oils are nowadays (I don't buy their arguments) and point to the now-infamous web site where filters were supposedly dissected and studied, and Fram supposedly coming out as the worst filters out there (don't buy those arguments, either)! /ubbthreads/images/graemlins/grin.gif
Count me as another who has used both! I've yet to use anything else in my latest Herald except Castrol 20W/50. So far, three years and 20,000 miles and the motor is as happy and strong as the day I bought the car. I do admit to preferring AC oil filters, but I'll use Fram without reservation.
Castrol 20/50w with Fram filters have always been the choice for all of my cars. Just basic good quality stuff.
[/ QUOTE ]But then there are those folks who will tell you just how horrible Castrol oils are nowadays (I don't buy their arguments) and point to the now-infamous web site where filters were supposedly dissected and studied, and Fram supposedly coming out as the worst filters out there (don't buy those arguments, either)! /ubbthreads/images/graemlins/grin.gif
Count me as another who has used both! I've yet to use anything else in my latest Herald except Castrol 20W/50. So far, three years and 20,000 miles and the motor is as happy and strong as the day I bought the car. I do admit to preferring AC oil filters, but I'll use Fram without reservation.
Alan_Myers
Luke Skywalker
Offline
[ QUOTE ]
I run my modern autos with sythetic oils. Does anyone know a reason why I should or should not run it in my TR4A and TR6?
[/ QUOTE ]
Hi,
This is a hot topic, with strong opinions both ways!
My 2 cents worth...
Generally speaking, I'd not use synthetics in old TRs, especially if the engine and drive train have some mileage on them.
I have several issues with modern synthetics in old motors:
First, many (most?) synthetics are "extended mileage" rated, which often means they are heavily loaded up with detergents. Those can "de-coke" the engine, and actually cause loss of compression and more blow-by around the rings. These old engines are designed to run best with a bit of coking. Even if you choose to use dino oil instead of synth, some of these are also are also "extended mileage" type and loaded up with a lot of detergents that can do more harm than good, so watch out.
A lower detergent synth might be okay. But, as others noted, synth oils are slicker and tend to cause external leaks. They also do the same inside the engine, tending to get past rings that have even modest wear, and down valve guides, into the cylinders. So you might see some oil burning after switching to synth, where the car was well-behaved running on dino oil.
With a newly rebuilt engine, synthetics are *definitely* wrong. Too slippery, they will almost certainly prevent the rings from bedding in on the cyl. walls, leading to glazing and an engine that will never reach full potential, unless it's rebuilt... again. Most say a *minimum* of 6000-9000 miles should be put on a rebuild, before switching to synth oils, to give all the engine internals a proper opportunity to bed in, seal and learn to play together well.
There have been a lot of reports of problems using synth oil in TR gearboxes, too. All I've heard have said that the box will very likely start popping out of gear on deceleration. Promptly switched back to dino oils, the gearbox generally will stop doing this and no lasting harm is done. Synthetic seems to be just too slippery here, too.
Also watch out for GL5 spec oils in the gearbox and tranny. Most have sulpher-based modifiers that will attack and eventually damage brass or bronze parts in the gearbox and diff. Use GL4, although it's getting harder to find. You might have to settle for an 85w95, instead of a straight 90w. 20w50 motor oil is about the same viscosity.
If motor oil is used in either place, it should be "racing oil" with no detergents, not just regular motor oil.
If your car has an overdrive, an A-Type especially, the gearbox oil needs a little more careful thought. Many now successfully use 20w50 "racing oil" in their non-OD 4-speed gearboxes. John Esposite at Quantum Mechanics, who has seen more than his share of gearbox and overdrive rebuilds, has done some testing and reported the results on his website. He seems to prefer straight 40w non-detergent (racing) oil, or even 30w if an OD is freshly rebuilt. The A-Type operates at much higher hydraulic pressures than the J-Type, so this is especially true for the earlier OD. He doesn't get into comparing synthetic with dino oil, last time I looked. However, since these ODs use an oil-bathed clutch, I'd personally avoid synth with it's extra slipperiness.
There are some specially formulated synthetic oils out there that might not have the problems mentioned above. Red Line is an example, with a wide line of very highly developed oils, some with reduced slipperiness to better work in gearboxes, etc. So, my only remaining beef is that synth can cost twice as much or more. I'd rather change the oil twice as often.
Heck, my TR4 made 120,000 miles (est., the odometer died at 98K) on dino oil with just a re-ring and bearing replacement at about 80K. I figure a the current rebuild, which will be kept lubed with decent quality dino oil, will likely last the rest of my life.
Note: I *do* use semi-synthetic blended oils in modern cars. I see some improved gas mileage an believe the viscosity holds up better between oil changes.
Mostly I use Valvoline oils, but I think there are many good brands out there. I avoid off-brand and recycled oils.
I run my modern autos with sythetic oils. Does anyone know a reason why I should or should not run it in my TR4A and TR6?
[/ QUOTE ]
Hi,
This is a hot topic, with strong opinions both ways!
My 2 cents worth...
Generally speaking, I'd not use synthetics in old TRs, especially if the engine and drive train have some mileage on them.
I have several issues with modern synthetics in old motors:
First, many (most?) synthetics are "extended mileage" rated, which often means they are heavily loaded up with detergents. Those can "de-coke" the engine, and actually cause loss of compression and more blow-by around the rings. These old engines are designed to run best with a bit of coking. Even if you choose to use dino oil instead of synth, some of these are also are also "extended mileage" type and loaded up with a lot of detergents that can do more harm than good, so watch out.
A lower detergent synth might be okay. But, as others noted, synth oils are slicker and tend to cause external leaks. They also do the same inside the engine, tending to get past rings that have even modest wear, and down valve guides, into the cylinders. So you might see some oil burning after switching to synth, where the car was well-behaved running on dino oil.
With a newly rebuilt engine, synthetics are *definitely* wrong. Too slippery, they will almost certainly prevent the rings from bedding in on the cyl. walls, leading to glazing and an engine that will never reach full potential, unless it's rebuilt... again. Most say a *minimum* of 6000-9000 miles should be put on a rebuild, before switching to synth oils, to give all the engine internals a proper opportunity to bed in, seal and learn to play together well.
There have been a lot of reports of problems using synth oil in TR gearboxes, too. All I've heard have said that the box will very likely start popping out of gear on deceleration. Promptly switched back to dino oils, the gearbox generally will stop doing this and no lasting harm is done. Synthetic seems to be just too slippery here, too.
Also watch out for GL5 spec oils in the gearbox and tranny. Most have sulpher-based modifiers that will attack and eventually damage brass or bronze parts in the gearbox and diff. Use GL4, although it's getting harder to find. You might have to settle for an 85w95, instead of a straight 90w. 20w50 motor oil is about the same viscosity.
If motor oil is used in either place, it should be "racing oil" with no detergents, not just regular motor oil.
If your car has an overdrive, an A-Type especially, the gearbox oil needs a little more careful thought. Many now successfully use 20w50 "racing oil" in their non-OD 4-speed gearboxes. John Esposite at Quantum Mechanics, who has seen more than his share of gearbox and overdrive rebuilds, has done some testing and reported the results on his website. He seems to prefer straight 40w non-detergent (racing) oil, or even 30w if an OD is freshly rebuilt. The A-Type operates at much higher hydraulic pressures than the J-Type, so this is especially true for the earlier OD. He doesn't get into comparing synthetic with dino oil, last time I looked. However, since these ODs use an oil-bathed clutch, I'd personally avoid synth with it's extra slipperiness.
There are some specially formulated synthetic oils out there that might not have the problems mentioned above. Red Line is an example, with a wide line of very highly developed oils, some with reduced slipperiness to better work in gearboxes, etc. So, my only remaining beef is that synth can cost twice as much or more. I'd rather change the oil twice as often.
Heck, my TR4 made 120,000 miles (est., the odometer died at 98K) on dino oil with just a re-ring and bearing replacement at about 80K. I figure a the current rebuild, which will be kept lubed with decent quality dino oil, will likely last the rest of my life.
Note: I *do* use semi-synthetic blended oils in modern cars. I see some improved gas mileage an believe the viscosity holds up better between oil changes.
Mostly I use Valvoline oils, but I think there are many good brands out there. I avoid off-brand and recycled oils.
I'll throw in my one cent worth riding on Alan's very detailed coattails. As a long term test of 20w-50 oils (primarily valvoline and changed at about 4k miles on average) my 90 Cherokee 4L six went 247k miles before breaking a rod just above the big end. (Precipitated I believe by my son learning to drive that same spring and killing the engine at least fifty times in the process.) The rod and main bearings looked great and the gap in the two top rings I measured were only .003 to .005 out of spec in the top of the cylinder. Have used straight 40w non det. oil in my A type overdrives for years with no problems. And as a cautionary note a shop changed my brothers transaxle fluid (an alfa), added GL5 and by the end of the summer was almost impossible to shift. Taken apart last fall all bushings and synchros had to be switched out. Pay your money take your chances.
Tom Lains
Tom Lains
I run synthetic oils for a couple of reasons.
#1 it get cold in Minnesota and I generally drive beaters in the winter. With Mobil 1 the motors always turn over a lot better then with regular oil, and if it turns well it will almost always start.
#2 I run a 400HP 455 Pontiac and have run 100's of lbs of nitrous oxide thru the motor at 125 and 175 hp levels.
Due to a couple of issues my oil level got low enough so that on nitrous I was uncovering the pump pick-up, the car was running with zero oil pressure when I noticed it on the gauge. I ran the motor for years after this with no trouble.
#1 it get cold in Minnesota and I generally drive beaters in the winter. With Mobil 1 the motors always turn over a lot better then with regular oil, and if it turns well it will almost always start.
#2 I run a 400HP 455 Pontiac and have run 100's of lbs of nitrous oxide thru the motor at 125 and 175 hp levels.
Due to a couple of issues my oil level got low enough so that on nitrous I was uncovering the pump pick-up, the car was running with zero oil pressure when I noticed it on the gauge. I ran the motor for years after this with no trouble.
myspitfire
Jedi Warrior
Offline
Quaker State,has a new product in quarts(all viscositys)with 'SLICK 50'all ready init.Running it without any problems.Its $2.44 qt at Walmart.I've also run synthetics without problems.I guess its according to the condition of the engine that causes leaks.I'm presently running 5w40(for fall & winter.As a matter of fact i've used slick50 in all my cars since it was introduced in 1979 when they originally sold a kit which included a quart of prep engine cleaner.When it was originally introduced it was $35.00.Never had a problem. /ubbthreads/images/graemlins/grouphug.gif /ubbthreads/images/graemlins/iagree.gif
LastDeadLast
Jedi Knight
Offline
Slick 50, along with all other "magic" oil additives, is junk. Change your oil regularly with a high quality oil.. I don't car if it's synthetic or otherwise and your engine will do fine.
All these snake oils do is temporarily mask a bigger problem and they definitely don't help protect your motor any more than conventional motor oil does. Ever wonder why the factories don't put these wonder fluids in new motors????
All these snake oils do is temporarily mask a bigger problem and they definitely don't help protect your motor any more than conventional motor oil does. Ever wonder why the factories don't put these wonder fluids in new motors????