Engine/Transmission (1994 - 1998) 310k should I change to synthetic

[Jschafer]

I have been reading a lot about the advantages of the synthetic oil and think I would like to go that rout, longer time between changes sounds good and better starting in this cold weather a plus also.



So my question do you think I should leave as is, (quaker 15-40 since new) with this many miles (310,689 miles approx) or make the switch?



One last thing where do I find the list of oil filters not to use.

 

[tp0d]

Changing to synth at that mileage is a bad idea. You will probably clog up more than a few filters with the junk the dino has left behind (dino deposits are not a real bad thing tho). The cleaning effect of the synth could possibly do some damage to places where the dino has built up. . I havent done this myself, have talked to an engine rebuilder about it, and he told me he's seen a few come in with plugged filters cus of it, and the motor loses circ and boom.



Best filter to use is the latest 24v filter, fleetguard with microglass or the wix works well for me. . hmm the wix number is 51607, fleetguard is LF587. I found an ebay link with all compatible filters. . I would not recommend fram, however. Heres the link with a list... http://cgi.ebay.com/ebaymotors/ws/e...tem=7915983104&category=33661&sspagename=WD1V





good luck



-j

 

[ABorchard]

Besides the sludge that might clog your filter there are most likely leaks that the sludge is plugging up and the synthetic will unplug. Unless you like chasing oil leaks stick with dino oil this late in the game.

 

[Vaughn MacKenzie]

I switched to synthetic at 352,000 for the first time. No problems. I changed the oil filter at 800 miles to be sure, and only ran it a couple thousand miles before changing it again. I used the "virtually synthetic" Rotella. Now with a couple of changes the oil is staying nice and clean for thousands of miles, planning to go 10k.



Vaughn

 

[LandShark]

I switched to synthetic at 90,000 miles. No problems.



My own opinion about the 'sludge' problem is that it's old thinking from the 1960's when sludge was more of a problem because of less efficient engines and less robust oils. If you have done proper maintence on your Cummins, there should be no or minimal sludge.

 

[Jschafer]

I have not had my oil pan off but the valve covers looked like new inside, no sludge what so ever. I change my oil at 6k intervals now and the oil is just starting to turn black.



Vaughn, how many miles are you running on the rotela between changes.



Any place I can find the oil filters NOT to use list?

 

[Vaughn MacKenzie]

Jschafer, I was running about 6-8k but I'm going for 10 now. As far as filters it's more like an "approved" list, which I don't recall what is on it. Good filters that come to mind are Wix and Napa, and I think Baldin is good too, but I don't think you can top the Fleetguard Stratapore filter.



Vaughn

 

[J Shocik]

From Jshafer:

310,689 miles 94 SLT 4x4

Taking this information into account, how long do you plan on keeping this truck?? If not for much longer, why spend the extra $$$ ?? You have over 310K mi. on QS oil, why change if things are OK?? The truck is used to this oil. After reading some of the responces, you all ready changed to the synthetic. You should have no problems, with the exception being a little lighter in the wallet.



As for the oil filter, I go with the recommended Fleetguard, which I buy from Geno's. I'm not trying to plug them, but it is factory recommended and fairly cheap from them. Just my opinion... John

 

[cyborg]

NOT RECOMMENDED!!

You should wait until the motor breaks in first.

Only kidding.



IMHO, Synthetic is better, in boats, bikes, jeeps, trucks, ect. Motors, gear units, hdraulics. It is more refined and cleaner. Not to be confused with high detergent which "cleans more". You've reached the 1/4 the cummins MTBF, so what the hhelll.

I've seen it said, I've said it before, I'll say it again, the price of fleetguards premium filter from cummins, genos or ??? is damn reasonable.



The difference between Baldwin and Fleetguard is like the difference between blondes and brunettes. They're gonna be a pain when you change them, either way.



Other oil filter brands? During a alcohol induced frenzy in the eighties, we cut up a bunch of oil filters by brand for analysis, CONCLUSION: Cheap filters are just that, cheap. Krapp. The other side was a couple of off brands had WIX canisters inside.



On edit: Of course what ever youve been doing can't be bad either.



peace

 

[Partyat33]

Only if you want your gaskets to leak. Thats just my humble opinion.



Dennis

 

[JBlock]

Not a good idea from all I have read, it may create leaks or worst yet engine problem with pluging oil path ways due to it ultra cleaning ablity.



You got 310K, and running, i would not change a thing.

 

[cyborg]

Not a good idea from all I have read, it may create leaks or worst yet engine problem with pluging oil path ways due to it ultra cleaning ablity.

Urban legend.



Up there with Ford owning cummins and Fram own Fleetguard

 

[SKargo]

Wow,

there's alot of bad, outdated information in this thread.

You can switch to synth at anytime. I like how everyone has "heard" this or "seen" that. Maybe people should refrain from offering advice unless they have 1st hand experience? Just a thought.



I have another vehicle with approx 300K miles on it, I put synth in it with no issues.

 

[Vaughn MacKenzie]

Wow,

there's alot of bad, outdated information in this thread.

I'm the guy who switched at 352k . . . no leaks at all. Camshaft is fine too



The camshaft discussion has come up before, I think this goes back to the 70s and 80s too when people switched on old dirty gassers when they shouldn't have. Never have heard of lube-related camshaft issues on a Cummins.



Vaughn

 

[SMorneau]

I had no trouble with a high miles toyota when I switched it over. I figure you can always put the old brand back in but I would expect any problems.



I would like to know what is in motor oil that would affect teflon. That stuff is compatible with just about everything.

 

[cyborg]

I remember reading that teflon is not solubile (?spelling?) and clogs the oil filters. And all teflon is filtered out of the oil before it can reach temprature to bond/attach to bearing surfaces to do any good.



Sounds right, but might be more internet BS.

 

[mjs]

I changed over at 225k oil pressure becomes more instant and i noticed on my ford 6. 9 that the pressure holds better when the motor temp is up high than the every day 15-40 oil . mjs

 

[MMeier]

Changed my 22 RE over at 230k, still does not leak anything or use any oil and the cam still has lobes on it, go for it!!

 

[J Shocik]

From SKargo:

Maybe people should refrain from offering advice unless they have 1st hand experience

I totally disagree with this as this is what makes this web site interesting!! All the different opinions!

I do agree there is a lot of "old and outdated" info being talked about here. The factory fill oil on ALL Corvetts is Mobil 1 synthetic oil, in a $50K car. That says something about synthetic oil.



As for my disagreeing with synthetic oil being put in this truck, it is purely a $$$ issue, synthetics being 2 or 3 times more expensive than conventional oils. 310K mi. w/no problems, if it ain't broke, don't fix it!! I would stay with the oil that got me there. Just my opinion... John

 

[SKargo]

From SKargo:



I totally disagree with this as this is what makes this web site interesting!! All the different opinions!

I do agree there is a lot of "old and outdated" info being talked about here. The factory fill oil on ALL Corvetts is Mobil 1 synthetic oil, in a $50K car. That says something about synthetic oil.



As for my disagreeing with synthetic oil being put in this truck, it is purely a $$$ issue, synthetics being 2 or 3 times more expensive than conventional oils. 310K mi. w/no problems, if it ain't broke, don't fix it!! I would stay with the oil that got me there. Just my opinion... John

So you say it's ok for someone who has no idea what they are talking about to offer up advice? I don't, and never will get that.

You might have a young guy, and maybe his truck is his first vehicle. He might listen to some bad advice, and then never come here again. Jus get the idea. t one scenario, but you