Grand Caravan w/ 3.3L V6 OCI

Joined
Aug 7, 2018
Messages
118
Location
WI
Hello all,

Vehicle described in the title, also in my sig. Currently has 208K on it. Runs flawlessly. Uses/loses very little oil. May have to add half a quart over an OCI which is currently about 3K/5-6 months. I work 4-5 days a week, round trip of about 32 miles, 85% of which is highway at 55+. Otherwise its city driving, so 30-45 and occasional short trips to the grocery store. Id sat I put on between 130-160 miles per week, depending.

Wondering about what I should go to for an OCI. Imm sure I can go a good bit longer than the 3K OCI I am doing right now. Ive been considering switching to 5K OCI and changing it once a year, maybe twice. Ive been stocking up on HDEO, mostly Rotella. A mix of T4 10w-30, 15w-40, T5 15w-40, and T6 5w-40 and 15w-40. IT just depends on what I could find where, and for what price. From what Ive read on here over time, any one of those could easily handle a 5k OCI, even the T4 conventional which from what I understand is actually more of a syn blend than a straight conventional.

I plan on running the 15w-40 during the summer, and during the winter thinned with 10-20% MMO if need be.

I just want to know if a 5k OCI is acceptable for this engine, or if I could even maybe go even longer than that. I plan on sending a sample to blackstone with my next oil change. My driving style is spirited, with the occasional WOT up to highway speed.
 
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Florida
With 208k miles, you clearly know what you're doing. Dodge Caravan engines are not renown for their reliability, but you might have one that slipped through. Keep doing what you're doing, with the exception of 3k OCI. I'd go 5k no problem. Even modern conventional oils can do that.
 
Joined
Dec 11, 2011
Messages
385
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I have a 3.8L that is very reliable, much like yours. I have 235K miles on the engine and have about the same oil consumption per oil change that you do (but at 5K intervals).

I think it's more important to look at hours run on the oil (I spend most of my time on the highway as well), but it's for hours on end. If you work out your average speed and hours on the oil, then send in samples at say 100 hours, 125 hours, etc. See what the lab results post up, and go from there.

Like rob1715 says, your current plan is working. So maybe not worry about changing your OCI ?
 
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One other thing, and not to jinx you.

The head gaskets will go before too long. Scrubbing from the aluminum heads on the cast iron block due to different rates of expansion and contraction make the head gasket more of a wear item than Head/Block combinations that are the same metal.

Mine gave out at 212K miles. Go with OEM gaskets and head bolts. Others may work, but with OEM you are in a better position to know your repair will last a long time. Bubbling in the coolant reservoir was the giveaway on mine, no other symptoms (other than bubbling "sound" behind dash, almost like low coolant).

Anyway, what year is yours?
 
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Jul 14, 2020
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5k should be fine, maybe 6k. When I worked in the express lube 10 years ago we had a ton of those vans come through. Lots of them extended oil changes to 7-10k miles but they were almost all barely showing any oil on the stick and extremely black. They seem to use oil if run too long between changes.
 
Joined
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Messages
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One other thing, and not to jinx you.

The head gaskets will go before too long. Scrubbing from the aluminum heads on the cast iron block due to different rates of expansion and contraction make the head gasket more of a wear item than Head/Block combinations that are the same metal.

Mine gave out at 212K miles. Go with OEM gaskets and head bolts. Others may work, but with OEM you are in a better position to know your repair will last a long time. Bubbling in the coolant reservoir was the giveaway on mine, no other symptoms (other than bubbling "sound" behind dash, almost like low coolant).

Anyway, what year is yours?
We saw lots of intake manifold leaks but maybe one head gasket failure. They were always considered a reliable engine other than that and tending to use oil if under maintained.
There is a coolant pipe underneath that rusts out and if it loses all the coolant you could overheat and take out the head gasket.
 

Cygnus_

Thread starter
Joined
Aug 7, 2018
Messages
118
Location
WI
One other thing, and not to jinx you.

The head gaskets will go before too long. Scrubbing from the aluminum heads on the cast iron block due to different rates of expansion and contraction make the head gasket more of a wear item than Head/Block combinations that are the same metal.

Mine gave out at 212K miles. Go with OEM gaskets and head bolts. Others may work, but with OEM you are in a better position to know your repair will last a long time. Bubbling in the coolant reservoir was the giveaway on mine, no other symptoms (other than bubbling "sound" behind dash, almost like low coolant).

Anyway, what year is yours?
2004. Always been very impressed with the way it runs.
 

Cygnus_

Thread starter
Joined
Aug 7, 2018
Messages
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Location
WI
We saw lots of intake manifold leaks but maybe one head gasket failure. They were always considered a reliable engine other than that and tending to use oil if under maintained.
There is a coolant pipe underneath that rusts out and if it loses all the coolant you could overheat and take out the head gasket.
I have that issue with the coolant pipe on mine. I have a bandaid on it right now. Used some loctite repair tape and it’s held Yup very well.
 
Joined
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Messages
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Mine doesn't have a coolant pipe like what you guys are talking about, at least that I remember or see in my pictures.

Here is a picture of the head off showing no sludge buildup or varnish with the 5K intervals (at least on the inside). The staining you see on the exhaust port is from a leaking valve cover gasket.


IMG_0785.jpg
 
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Joined
Feb 28, 2018
Messages
13
Location
Michigan
Hello all,

Vehicle described in the title, also in my sig. Currently has 208K on it. Runs flawlessly. Uses/loses very little oil. May have to add half a quart over an OCI which is currently about 3K/5-6 months. I work 4-5 days a week, round trip of about 32 miles, 85% of which is highway at 55+. Otherwise its city driving, so 30-45 and occasional short trips to the grocery store. Id sat I put on between 130-160 miles per week, depending.

Wondering about what I should go to for an OCI. Imm sure I can go a good bit longer than the 3K OCI I am doing right now. Ive been considering switching to 5K OCI and changing it once a year, maybe twice. Ive been stocking up on HDEO, mostly Rotella. A mix of T4 10w-30, 15w-40, T5 15w-40, and T6 5w-40 and 15w-40. IT just depends on what I could find where, and for what price. From what Ive read on here over time, any one of those could easily handle a 5k OCI, even the T4 conventional which from what I understand is actually more of a syn blend than a straight conventional.

I plan on running the 15w-40 during the summer, and during the winter thinned with 10-20% MMO if need be.

I just want to know if a 5k OCI is acceptable for this engine, or if I could even maybe go even longer than that. I plan on sending a sample to blackstone with my next oil change. My driving style is spirited, with the occasional WOT up to highway speed.
Don’t overthink this. I put 300,000 miles on my Chrysler van running standard Pennzoil 10w30, changing the oil & filter every 5000 miles. 5w40? Thinning with MMO? Just follow the manufactures recommendation and forget it.
 

Cygnus_

Thread starter
Joined
Aug 7, 2018
Messages
118
Location
WI
Another quick question for you all here. Is there any reason not to use a higher capacity or larger oil filter than it calls for? On these vans there is plenty of space for a taller (longer) oil filter than what is used by standard. I found one that is close to twice the length of the standard, everything else is the same.
 
Joined
Jan 28, 2022
Messages
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My 2006 3.3L hit 300K miles this week. It has been run on various PQIA approved brands of 5 or 10 w - 30 or 10w-40 conventional or synblend oil since I owned it at 113K in 2013 and is mainly highway driven. The oil has been typically changed around 6000 miles with a Fram ultra oil filter changed every other change and uses a quart of oil during the interval. I always use a Wix air filter and transmission fluid change with a wix filter at the recommended 60 K service interval. Both motor and transmission are the original and are still running flawlessly.

As for a larger oil filter adds about 1/3rd of a quart to the 5 quart sump. Unless your car is a major oil consumer where you might intend to run longer intervals for the reasons of economy I really see no reason to consider it.

The only common denominator is see among users that is consistent is the reluctance to use 20 weight oil in the Mitsubishi OHV pushrod engine which was designed in 1990 to use 10w-30 oil.
 
Joined
Dec 11, 2011
Messages
385
Location
USA
Another quick question for you all here. Is there any reason not to use a higher capacity or larger oil filter than it calls for? On these vans there is plenty of space for a taller (longer) oil filter than what is used by standard. I found one that is close to twice the length of the standard, everything else is the same.
Again, if you haven't had issues, why change filters? I use Mopar MO-409 from Walmart and with over 235K miles now I have no oiling issues and no oil related issues.

It's your van though, so if that is what you want to do, then try it and see. Worst that can happen is it trashes your engine, best it can do is the same as stock.

Filters have different sizes and shapes for a reason and without knowing the exact specifications of the filter (ADBV, ADBV type, pressure relief specs, etc.) you are most likely taking a guess at what will work for a slight gain in capacity?

If you want more oil capacity, the Jeep 3.8L oil pan holds one more quart than the van oil pan.
 
Joined
Feb 28, 2018
Messages
13
Location
Michigan
Don’t overthink this. I put 300,000 miles on my Chrysler van running standard Pennzoil 10w30, changing the oil & filter every 5000 miles. 5w40? Thinning with MMO? Just follow the manufactures recommendation and forget it.
 
Joined
Feb 28, 2018
Messages
13
Location
Michigan
Full agreement. My Chrysler has 304,000 miles using yellow bottle Pennzoil. I change the oil &filter every 5000 Miles. This is simple. Don’t go out of your way to create complexity.
 
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