switching to synthetic motor oil?

Because im a cheap bastard i didnt use synthetic in this VW 1.8 turbo.
Lesson learned, it is very sludged up and speaking with a true vw mechanic he repairs alot of these engines including removing the pan to try to clean the pick up screen for the no synthetic users....like me.
well what happens is the turbos run at very high temps and the normal oil sludges due to this. synthetics wont sludge and that truly is an advantage to synthetic oil.
im going to splurdge this time. with non turbo engines normal oil is fine

Eric, I have over 200K on my turbo diesel 1995 Suburban and have always used the dino oil. Is the 15-40 diesel oil made so it doesn't sludge with the high temp of the turbo?

Good thread men. This answers (sort of) part of my question over on the alignment topic.
Eric, my problem is I have no manual. It sounds like the dino 15-40 that I buy 300gal at a time will work well with my '85 454. We run in some cold weather here in MI during April and Sept/Nov.
Anyone know what the manual says for the older 454's?

Tom, Thanks I never knew that the diesels exhaust ran cooler than gas. Is it just the combustion temp of diesel?

Eric, At least with my 95 with the door bottoms rusting off I won't get the extra dummy charge if I use it to pull a boat in to your shop for repair!! It has given me good service and I do not have a fancy car in the garage!

Not quite Pete,

The diesel charge is flooded with air and only a portion is used for combustion, the rest is mass that absorbs the heat of combustion and expands, thus cooling itself. Unless one is WOT and fully fuelled, and using up all the air, then combustion temps can see 11-1300.

But at WOT, a gas turbo sees a few hundred even more than that, I believe.

Plus ,the greater expansion incurred in the diesel exhaust stroke tends to cool things down before they hit the turbo.

Thats why on your truck if you up the boost via wastegate and leave the max fuel alone, EGT drops.

Pistons dont like 1500 degrees for long periods of time no matter what fuel you burn. My cummins diesel is only slightly modifed and I can peg my 1500 degree pyrometer. Just normal intown driving it will see 900-1000 and crusing highway unloaded about 600-700. That is a big reason I chose syn for the truck. Go with rotella T and you cant go wrong for either vehicles.

eric lavine wrote: another good one... the school warned us about the old detroit diesels running away, well my cousin was going to school with me and he set up the govonor on a 6-71...i believe... well they fired that thing and it shot up to about 20000 rpms and they shut the intake door over the blower and it started sucking oil internally and burning the oil as a fuel. its one of those things that stick in your mind and you dont forget the sound that thing made or the white smoke it was blowing from the oil burning

How did you shut it down, or did it blow up?

We've had the same thing happen on a 4-53 Detroit on one of uor fork lifts. An oil line broke to the blower. The oil goes strait to the cylnders and acts as the fuel. The emergency flip door on the intake of the blower shut it down before it blew up. You've never heard an engine scream until you've witnessed this.
Anyone ever witnessed a Detroit accidentally run backwards?

its something you wont forget, they finally shut it down with a fire exstingusher, it was a 150000 sq ft building and it was filled with thick smoke

Im not sure Jim, for some reason that sticks in my head. next time you get some read the contianer cause im curious too. im 50/50 on this one

IIRC, the HD stands for High Detergent. If it says just 40, or 30, it doesn't have detergents.

im looking at an oil right now and it i says SAE ND 30, it says non detergent, so its a matter of reading the labels, a good qaulity oil will always have the API, certificate on the container. if it doesnt stay clear of that oil. read where they were manufactured and alot of the oils are the same just labeled differently and priced accordingly

On either the History or Discovery channel, there recently was a show on lubricants. The shows explained that synthetic oils were developed for use in a wide variety of as well as extreme conditions where regular oils would not perform as needed or hold up over time.   The show explained that standard oil has impurities in it that attract moisture and dirt that bonds with the molecules over time as the oil breaks down. Additves help to address this. On the other hand, synthetic oils are made in very controlled precesses resulting in very uniform molecules which provide the lubricating properties and life based upon design.

Based upon the above as well as feedback I have heard from both users and mechanics, I am now a believer in synthic oils. I use syntheics in my truck and I am planning on switching to synthetic oil as soon as my 05 Nautique engine is out of warranty. I still plan on changing the oil every 50 hours since the inboard engine is "always under a load" when running as well as sits underneath the cal in a hotter than normal environment.