Idiot me, put in wrong oil month ago, OK to leave?

Mongler98

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Joined
Mar 23, 2011
Location
COLORADO (SE of Denver)
TDI
98 Jetta TDI AHU 1.9L (944 TDI swap in progress) I moved so now i got nothing but an AHU in a garage on a pallet.
Huh? So you're saying that adding a heavier oil to a lighter oil won't change the viscosity? Stay in school kids.
Topping off a already full oil pan will do NOTHING. If you had say the lowest on a dip stick you can have with out damage to the engine, adding a heavy oil to it might change it SLIGHTLY but will AT MOST be no more than by 25%. So your saying that a 5-30 add in at most 1 quart of 15-50 should theoretically increase the viscosity by NO MORE than 5. i fail to see how this will do anything other than waste money and basically do NOTHING.

Motor oils are MUCH more complex than just a simple # rating. I would rather have a 5-30 in my TDI than some mixed up oils that may have an adverse reaction to the chemistry involved in synthetic oil mixtures.
 

turbobrick240

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Joined
Nov 18, 2014
Location
maine
TDI
2011 vw golf tdi(gone to greener pastures), 2001 ford f250 powerstroke
^ Synthetic oils are by and large compatible with each other. XOM wouldn't use an additive package in one mobil1 product that would have an adverse reaction with another mobil1 product. Adding a quart of M1 15w50 to 4 quarts of M1 5w30 would probably bring the properties of the blend pretty close to within the 5w40 range. Not necessary, but certainly not harmful. Do some reading over at Bob is the oil guy. Hint: tribology is not the study of native americans. :)
 
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AndyBees

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Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
I have a container at my garage that I invert each emptied oil bottle/jug to let them drain completely......... all blends, weights, brands, etc. I use it to add to the engines of my mulcher, mowers, pressure washer, generator, etc. Even with the small number of oil changes I do for myself and others, I'll accumulate about a gallon per year. I never considered compatibility to be an issue.
 

Mongler98

Top Post Dawg
Joined
Mar 23, 2011
Location
COLORADO (SE of Denver)
TDI
98 Jetta TDI AHU 1.9L (944 TDI swap in progress) I moved so now i got nothing but an AHU in a garage on a pallet.
I have a container at my garage that I invert each emptied oil bottle/jug to let them drain completely......... all blends, weights, brands, etc. I use it to add to the engines of my mulcher, mowers, pressure washer, generator, etc. Even with the small number of oil changes I do for myself and others, I'll accumulate about a gallon per year. I never considered compatibility to be an issue.
I see nothing wrong here.
Any issue I would have is if the engine or pump etc... Calls for NON Detergent oil.
Mixing oil was not much of my concern as it is more of a waste of money. I have a bad taste in my mouth from when I was a kid; my dad had a MINT vw supper bug, with 28K miles on it that we took to shows and what not. This was back in the early 80's and my dad needed to top off the oil. He made a mistake and got a can of SAE 30 vs the 10/40 that was in it. After he added it he realized the error and said, heh it’s probably fine. On the drive home, not even 40 miles into the 200 mile trip, the engine threw a rod out the side and into the tire, he lost control of the car and put it right nose first into a guard rail. Completely totaled. I had a gash on my head and his baby was totaled. He had it hauled home so he could find out what the hell happened. SPUN BEARINGS. Now this car was OEM all original with 28K miles on the clock. Best conclusion, it was the added oil. He said he only had to add 1/2 the can. So who knows if it actually was the issue but I never mix oils due to this sad story from my youth.
Add whatever the heck you want.
 

turbobrick240

Top Post Dawg
Joined
Nov 18, 2014
Location
maine
TDI
2011 vw golf tdi(gone to greener pastures), 2001 ford f250 powerstroke
I see nothing wrong here.
Any issue I would have is if the engine or pump etc... Calls for NON Detergent oil.
Mixing oil was not much of my concern as it is more of a waste of money. I have a bad taste in my mouth from when I was a kid; my dad had a MINT vw supper bug, with 28K miles on it that we took to shows and what not. This was back in the early 80's and my dad needed to top off the oil. He made a mistake and got a can of SAE 30 vs the 10/40 that was in it. After he added it he realized the error and said, heh it’s probably fine. On the drive home, not even 40 miles into the 200 mile trip, the engine threw a rod out the side and into the tire, he lost control of the car and put it right nose first into a guard rail. Completely totaled. I had a gash on my head and his baby was totaled. He had it hauled home so he could find out what the hell happened. SPUN BEARINGS. Now this car was OEM all original with 28K miles on the clock. Best conclusion, it was the added oil. He said he only had to add 1/2 the can. So who knows if it actually was the issue but I never mix oils due to this sad story from my youth.
Add whatever the heck you want.

Interesting story, but I highly doubt the 30 weight had anything to do with the spun bearings. 10w40 was a pretty crappy oil back in the day. That oil was more likely at fault. Those air cooled boxers didn't run forever anyhow- the nice thing was that it only took a couple of hours (or less) to swap in a new one.
 
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AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Back in the day when I was much younger, I dabbled with mud-buggies, rail jobs as some people called them. We'd work on them three or four nights a week and then tear them up on the weekend.

Anyway, I built a nice engine for my buggy. After doing a few weekends, I changed oil at my uncle's garage. He had some bulk oil in 55 gallon drums. He also had some hydraulic oil in 55 gallon drums ......... Yep! I used the wrong stuff. On the next weekend out, by the time the last day was over the idiot oil light was flickering at idle. When we got back to his place, I was really scratching my head as to what was wrong... changed switches, etc. Then, finally figured out that I had used the wrong oil. We disassembled the engine to find rod and main bearings showing red....
......... very, true story! This was a really hopped-up engine.. lots of dollars invested!
 
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