Currently running 10/30 Castrol but am wondering to switch to 15/40 Rotella or 15/50 Mobil 1. This is a fresh total rebuild. If I do choose the synthetic route should there be an amount of miles put on the engine before the switch? Currently I have about 400 miles on the rebuild. THere was an oil change after break in (30 minutes) as well.
I would wait a couple of thousand miles, At least 1000...If you go to syn now and your rings are not seated it will take forever for that to happen... I would stay away from the 50 weight oil. What is directing you go to the heavier weight? Have oil pressure issues? If all is well with the oil pressure with 10 30...I would stay that route, I always run zinc additive.
i agree . as soon as i read that i could not see the reason for the heavier oil after a rebuild . unless you are rebuilding for kinda extreme rpm/hp output . yep - careful on your break in oil selection ( several companys now have oil specifically for that i think - edelbrock , joe gibbs , comp maybe also ) and some guys swear by non detergent 30 weight as a break in lube . also agree on the 1000-3000 miles and then switch over to the synthetic timeframe . and part of the plus on synthetics is that you get the same amount of protection with less viscosity , less oil weight = free horsepower and faster initial circulation upon startup , especially in colder weather . so you may be able to use a 5w20 oil . one downside that i have found is that when putting in oil additives the synthetic has a long change interval and sometimes the additives do not last that long , only the normal 3000-4000 miles . lucas does have a synthetic additive that i've used that seems fine . i've been using synthetics in probably 6-7 vehicles since 1993 .
Right now I am running the ZDDP additive by lucas but would like to run a little more heavier oil for some extra oil pressure. I have 10-15 at idle and would like a little more. I have the TA timing cover and oil pump that is supposed to give me more psi at idle and it is not giving the results. So this is the reasoning for my thinking.
I would be investigating your oil system then, on a fresh rebuild now is the time to identify all issues so you can get your motor where you would like it for the remainder of the current overhaul. I have about 10-15psi at idle as well with 10w-30 but that is with a bone stock 40 year old system on an engine with 46,000miles
Read up on all the ZDDP issues (Re: When/if to switch to synthetic) Dear tobyp and V-8 Buick members, You might want to have a look at this thread started by engine guru Jim Weise: http://www.v8buick.com/showthread.php?t=222499. In the presentation that Jim attended, the representative felt that there wasn't any real gain for an older engine in using synthetic oil because these engines very unlikely to reach the temperatures where "dino oils" start to break down. On the other hand, the presentation indicated that simply adding ZDDP additives may not have the desired effect because modern oils will simply "wash" the ZDDP away. As Jim noted, this was a vendor of specialty oils for classic cars, but still the points made about how detergent can undermine ZDDP seem valid. If your rebuilt engine doesn't have roller rockers, you should be especially careful to make sure your engine is properly supplied with ZDDP. The 300 cid in my 65 Special wagon is dying after only 10 years and barely 50,000 miles. There are probably other factors, but undoubtedly ZDDP deprivation played a part. What I'm hearing through the grapewine is that there is something of a engine failure epidemic among classic cars. So don't let it happen to you! :af: Cheers, Edouard
I have heard (and info on the oil bottles seems to confirm) that Mobil 1 15-50 has extra zinc in it, compared to the lower viscosity Mobil 1's.
we did have a customer that used mobil #1 15-50 in his diesel ram 3500 trucks . they had a few and they haul'd alot of distance . they even pulled the stock tranny's out and installed special h-p tq converters etc . they did their homework pretty good so maybe thats correct . mobil would kinda have to keep up as far as truck oil .
I use Mobil 1 15-50 synthetic in My Ram srt-10 (viper engine) and it is great, but I only drive the truck in the summer. I'm guessing most classics aren't driven in the winter but if you live in a cold winter climate and dive your car year round, outside temps factor in!
I'm switching to synthetic after 4,000 miles, mostly because so far the engine hasn't leaked or used a drop of oil, and I think the rings are about sealed from how I've used the engine in the last 4,000 miles. If it starts leaking or using oil, I'll go back to conventional. I get single digit temps or lower here all winter and 110*F+ temps where I drive in the summer.
Okay, I'll ask too! (Re: When/if to switch to synthetic) Dear SilverBuick and V-8 Buick members, Okay, I'll take the bait! :grin: I confess, when I had the ol' 300 cid rebuilt in 2000, I also decided to go synthetic figuring it would give me a longer life (little did I know about "ZDDP" ).So, I do have the synthetic "itch." :grin: Still, I thought I was convinced by the argument that dino oil provided adequate protection unless you were running it either in a racing engine or a very small 4-banger that really was going 6000 RPMs. So tell me SilverBuick, why are you switching to synthetic? Is it purely because of the external temperature extremes your Buick will have to cope with or . . . . are you suspicious with the claims that dino oil is just as good for our "mature technology engines?" Awaiting your reply with baited breath!! :laugh: Cheers, Edouard :beer
Re: Okay, I'll ask too! (Re: When/if to switch to synthetic) I think it has better temperature control, less water absorbtion, and I am running a roller cam and I can get lazy on the oil change intervals at times. Also I'd consider mine racing from time to time. Just put 3,800 miles on the engine in 9 days drag racing five of those days. I was winding it up to 6,000rpm on the last day. So far, cruising at 2300rpm it has 55psi of oil pressure and hot 190*F idle (after hours of highway driving) oil pressure is a bit over 20psi using 10w-30 oil. I'm pretty happy with this assembly, I finally got a second one right! If it leaked or used oil, I wouldn't bother based on cost. I have 60,000+ miles on my Centurion engine since I rebuilt it in 2002, using nothing but off the shelf dino oil, never got a drop of ZDDP additive, ever. Had one or two changes that it got synthetic, but the synthetic leaks out the rear main, dino oil doesn't. Go figure. Anyways where I'm going with this is I "temporarily" put that engine in my skylark for a few months (because I didn't need a convertible in the winter) and before I put it back in the Centurion I figured I'd give it new gasket and bearings just because it had at the time 50,000 miles (it idles at 600rpm with 15-20psi with 10w-30, so just because). So I openned it up, the bearings all looked fantastic, the cam looked shiny and good, no apparent wear, though I didn't take a mic to the lobes, didn't see one cupped lifter, all had a nice circle pattern showing they spun freely, so they went back in the engine, and all has been good since. Has about 60,000 miles now and still is just purrs and runs great. I also run a vacuum gauge on it, and worn lobes often show ticks with a gauge, this one has none. I've got a '67 T-bird I've personally put 20,000+ miles on the 428FE that I've never openned, but like the Centurion it's always gotten regular dino oil and I've ran a vacuum gauge and it show's no ill effects so I'm guessing the cam isn't wearing abnormally. I'm not conviced that ZDDP has a huge effect until valve spring pressures get high. The Centurion has 110lbs on the seat, and I'm sure the T-bird's isn't much more than that, especially after fourty years. I've also ran a TA118 cam with 110lb springs on dino oil, no ZDDP for 25,000+ miles and that cam still looks new and the flat tappet lifters, like the Centurions, have a nice circle pattern on the bottom and aren't cupped at all. The 212 cam I just pulled out after 10,000-12,000 miles looks good too, and it saw no ZDDP additive either, ever. Maybe I'm just lucky though. I did eat two 290-08H cam's though back to back, but I'm pretty sure that was from coil bind, I knew my springs were very borderline when I installed them, that's why the switch to the TA212.
Re: Read up on all the ZDDP issues (Re: When/if to switch to synthetic) simply put if youre going to add zddp addtive make sure you buy oil with no calcium detergent in it. or buy oil that already has the zddp. you can get summit brand dino oil that has zinc in it. I sell amsoil break-in oil, along with z-rod oil which has zddp along with rust prohibitors
My opinion and that's not worth much, but after 45 yearss of playing different oils, run the lightest weight you possibly can. Thick oil robs HP and is slow to lube on startup. I have run Mobil 1 since it first came out. I have run 10W30 in everything from race cars to motorhomes and all my passenger cars. I have never lost an engine with a bearing or oil related problem and I'm talking dozens of vehicles with 200,000+ miles and never touching the engine. I have a 97 Ford Ranger with 385,000 miles and an untouched engine that has only had 5W20 Motorcraft Blend used in it. I bought it for my step-daughter with 350,000 on it and was told it had only been serviced by this one dealer. I take the VIN there and they pull it up, there were pages of service and that was the only oil and Motorcraft filters were used. Now for you, you face the same problem I do with my race car. You have to have the additive for the flat tappet cam. I had to go away from Mobil ! a few years because of that. I now use Brad Penn 10W30. I just built a 350 Buick for another car and I started it on Joe Gibbs Break-In oil and will switch it to Brad Penn after one more trip to the track. The real answer is to run a roller cam like all the new car stuff. I will never build another engine of my own with out one. Don't want the oil hassle. 2 cents. Jim N.
For all of us in the north that have to deal with frigid temps in the winter, there is an easy 'test' to do to show one of the benefits of synthetic oils. Put 2 unopened qts. of oil in the freezer over night....one synthetic and one regular. Next day, shake them up. It will be pretty obvious which one you want in your oil pan when it's negative degrees outside.:TU:
So IS there a good synthetic with low calcium and high ZDDP (or ZDDP additive compatibility) and a 10w-40 or 10w-30 rating at anywhere near a reasonable cost? JB
I beleive from reading this I will do a Mobil1 10w30 with STP engine oil treatment. Mike from TA has good things to say about the STP ZDDP levels.
i use castrol gtx 10w40 and add zddp in the buick engine. i cannot see any benefit, in my case, to use synthetic oil. now i do use castrol syntec on my '08 astra and '11 cruze. of course i wait until that oil is on sale to purchase it.
You will never get me away from synthetic oil unless it is a worthless vehicle like the 87 Cutlass that I bought for $300. for my step-daughter to start learning to drive in and I only use the cheapest NAME BRAND oil I can find in it and it has been fine for 6 years, but anything I really care about will have synthetic. I ran Mobil 1 10W30 in a 455 in my 68 and my 67 (same engine not torn down) for over 5 1/2 seasons and only took it apart then because it had a broken rocker/lifter/lifter bore. The bearings still looked good. That engine had 1,000s of runs on it, mostly 1/4 mile. I would run bracket races with it where you did not get to cool any between rounds and the water and oil temp would get high after 5 or 6 rounds. I was racing 3 or 4 times a week + going to National races too. I just feel it gives you the protection you need. For street drivng the extended drain time will pay the difference in cost. Now if you are doing short-trip and low miles/time, it may not pay. But my street cars are driven 10+ miles 95% of the time they are cranked. Jim N.
