Back when I was in collage. Myself, and others put together a Masters study=
on oil filters. And at the length of service. And at what point that the o=
il filter bypass would be opened. We drilled a lot of holes in engine block=
s for gauges. Part of the study used cars from all of the big 3 back then.=
I was alittle surprised how all 3 brands were so similar in bypass opening=
. The filter medias in general. Where getting restricted to the point that =
bypass's valves. Started at about 2400 miles. All engine where equipped wit=
h PCV's installed. This is an extremely short, and general e-mail of a ve=
ry long review of the paper. Bob Dunahugh 78 Royale _________________=
_______________ From: Bob Dunahugh Sent: Monday,=
April 29, 2019 5:09 AM To: gmclist Subject: RE: Synthe=
tics are great. But I don't see them in our old dirty engines Matt. Ho=
w often do you change your oil filter? Bob D _______________________=
_________ From: Bob Dunahugh Sent: Sunday, April 28, 2019 11:52 AM To=
: gmclist Subject: Synthetics are great. But I don't see =
them in our old dirty engines I think nowadays, most manufactures re=
commend synthetics for the engine that are produced today. Yes. Both the ol=
d/new engines have pistons that go up, and down. And a crankshaft that goes=
round, and round. But after that. It's a different world. Look how small t=
he oil filters are. And how long the oil change cycles are. These new engin=
e run extremely clean inside the crankcase. As to oil contamination. Ou=
r engine are of a different design. That produce much more of these damagi=
ng crankcase oil contaminants. You help to negate some of what these con=
taminants do to you engine. Simply by removing them by more frequent oil/fi=
lter changes. Using synthetics simply doesn't change this situation. I put =
the Howell/GM EFI system on our 403. I've noticed that my oil stays cleaner=
, longer. But even after adding the EFI. I haven't lengthened my oil change=
intervals. YES. I'm a NUT on oil changes. But I seem to get some benefits.=
As an example. I have a 98 Chevy Astro that was used for one of our busi=
nesses. Then our daughter used it for some year. Now I'm back to using it. =
I like it. The interior/seats still look great. Oil/filter changes have alw=
ays been in the 3000 mile range. The odometer is now at 324,000 miles. Hot=
oil PSI are at 50. Never add oil between oil changes. That 4.3 Chevy V6 ha=
s never been apart for anything. Always had the same old 10W-30 used in it.=
Planning on a trip to Kansas/Oklahoma from Iowa in the next few weeks with=
it. As to synthetic oils. Use them. Just don't go over 3000 miles on an o=
il change. Bob Dunahugh 78 Royale
on oil filters. And at the length of service. And at what point that the o=
il filter bypass would be opened. We drilled a lot of holes in engine block=
s for gauges. Part of the study used cars from all of the big 3 back then.=
I was alittle surprised how all 3 brands were so similar in bypass opening=
. The filter medias in general. Where getting restricted to the point that =
bypass's valves. Started at about 2400 miles. All engine where equipped wit=
h PCV's installed. This is an extremely short, and general e-mail of a ve=
ry long review of the paper. Bob Dunahugh 78 Royale _________________=
_______________ From: Bob Dunahugh Sent: Monday,=
April 29, 2019 5:09 AM To: gmclist Subject: RE: Synthe=
tics are great. But I don't see them in our old dirty engines Matt. Ho=
w often do you change your oil filter? Bob D _______________________=
_________ From: Bob Dunahugh Sent: Sunday, April 28, 2019 11:52 AM To=
: gmclist Subject: Synthetics are great. But I don't see =
them in our old dirty engines I think nowadays, most manufactures re=
commend synthetics for the engine that are produced today. Yes. Both the ol=
d/new engines have pistons that go up, and down. And a crankshaft that goes=
round, and round. But after that. It's a different world. Look how small t=
he oil filters are. And how long the oil change cycles are. These new engin=
e run extremely clean inside the crankcase. As to oil contamination. Ou=
r engine are of a different design. That produce much more of these damagi=
ng crankcase oil contaminants. You help to negate some of what these con=
taminants do to you engine. Simply by removing them by more frequent oil/fi=
lter changes. Using synthetics simply doesn't change this situation. I put =
the Howell/GM EFI system on our 403. I've noticed that my oil stays cleaner=
, longer. But even after adding the EFI. I haven't lengthened my oil change=
intervals. YES. I'm a NUT on oil changes. But I seem to get some benefits.=
As an example. I have a 98 Chevy Astro that was used for one of our busi=
nesses. Then our daughter used it for some year. Now I'm back to using it. =
I like it. The interior/seats still look great. Oil/filter changes have alw=
ays been in the 3000 mile range. The odometer is now at 324,000 miles. Hot=
oil PSI are at 50. Never add oil between oil changes. That 4.3 Chevy V6 ha=
s never been apart for anything. Always had the same old 10W-30 used in it.=
Planning on a trip to Kansas/Oklahoma from Iowa in the next few weeks with=
it. As to synthetic oils. Use them. Just don't go over 3000 miles on an o=
il change. Bob Dunahugh 78 Royale