[Kevin1990]

Gentlemen,

i´m rebuilding my Saratoga´s 3.0V6 this summer. Means complete gaskets getting replaced, new timing belt / wapu, lifters etc.

I always used fully synthetic 10W 40, 5W 50 will be the new oil with the new lifters.

Are those Mitsu engines designed for high mileage?
Or should i also replace the main bearings?

I found some 300 000 mile 3.0 V6 vehicles, but i don´t know what already has benn done or overhauled.


Would be interesting to know...


Greetings
Kevin

 

[John Wood]

300,000 miles shouldn't be a problem and you could probably go much further with good maintenance. I had the heads off my 3.0 just before it hit 200,000. There was not only no ridge at the top of the cylinders, but I could still see cross hatch marks on the cylinder walls. I hear that the steel used in the Mitsu engines is pretty good. I may end up taking mine to near 300K if it works out.

 

[B10alia]

If you have the engine out of the car, it's a good idea to mike all the major wear components and check to make sure they're still in spec.
Really the biggest determiner of engine longevity is maintenance. If you've been up on yours, chances are you'll find very little wear and things should be fine. The 6G72 is a decent engine. Mitsubishi made some engines that weren't really spectacular (i.e. the 2.6 found in the early K's), but I wouldn't say they're bad engines. I prefer the 2.5 because... well it's an American pride thing, mostly, but that is a truly bulletproof design that belongs up there with the slant six for reliability. That being said, I would still buy a 3.0 car. Really the biggest problem with the 3.0 was the valve seals. So does it equal the 2.5 in reliability and ease of maintenance? In my book, no. Is it a ticking time bomb like the early Ford SHO V8's (very bad issues with the camshafts)? Far from it. I would say it's an above average engine.

 

[Kevin1990]

Well that´s nice to hear!

The engine would stay in the car, trans is still working, TCC is done, bump upshifts til 3rd (bearings gone), but it will stay in the car.


@B10alia: Well, i´m kind of a "forced fan" of the 6G72 in Chrysler vehicles. because i got them in both of my vehicles. My personal favorite engine ever used by Chrysler is the LA 318, especially found in AHB M Bodies. I´d also love to have a 3.3 / 3.8 in my garage,

But i prefer a classic and tougher trans. OK, i take extremly good care on engine and trans, maybe a bit "too much",....so a 3.0 bolted on a A 670 would be my perfect daily, but not much vehicles featuring this option were sold here in Austria. So i´m pretty much forced to drive an oil burning, worn out A604 having vehicle.....but before i see my first car on a yard, i´ll fix thing that should be fixed....


Thanks !

 

[1991spirites]

A friend of mine had 250k miles on his 3.0 in his 95 Caravan. The motor was original except timing belt, water pump, and other basic maintaince items. I helped him to valve cover gaskets on it because they started leaking and when we pulled them off the gaskets still had a Mopar part number on it and that was at 245k miles!!

 

[Kevin1990]

A friend of mine had 250k miles on his 3.0 in his 95 Caravan. The motor was original except timing belt, water pump, and other basic maintaince items. I helped him to valve cover gaskets on it because they started leaking and when we pulled them off the gaskets still had a Mopar part number on it and that was at 245k miles!!

That´s a lot!

I only got arround 125k miles on it now....but 20 years are 20 years for any gasket....i replaced the valve cover and oil pan gaskets arround 95k miles (ca. KM ~ Miles).
But it leaks oil arround every cam and crank seal, head gasket (oil and water is clean) and of course the valve stem seals.

So a complete "rebuild", or lets say a complete gasket tune up is necessary.

 

[neon98rt]

i changed stuff too due to it being 20 years. I had the transmission gasket, oil gasket and valve cover gasket. The car does not leave an oil puddle but it is still oily on the bottom. I figure every month i dont give the bank 300 or more dollars paying for a new car is money in my pocket. I have 104k miles on my 90 lebaron. I have put a lot of money in the car. name a part and i replaced it. Go ahead name a part. ( part as in maintenance parts) .
I also treat it like a sports car so hopefully i still will get another 100k out of it.

 

[Kevin1990]

i changed stuff too due to it being 20 years. I had the transmission gasket, oil gasket and valve cover gasket. The car does not leave an oil puddle but it is still oily on the bottom. I figure every month i dont give the bank 300 or more dollars paying for a new car is money in my pocket. I have 104k miles on my 90 lebaron. I have put a lot of money in the car. name a part and i replaced it. Go ahead name a part. ( part as in maintenance parts) .
I also treat it like a sports car so hopefully i still will get another 100k out of it.

Well, i also spent a lot (maybe too much for a 500 $ car) of money....but i tret it like it supposed to be treated, but the oil consumption and especially the leaking problems are too massive.
Maybe there´s good hardware in the engine, but the gaskets ans seals fail too early.

That´s why i expect arround 300 000 KM (not miles), beacause we got a lot more stuff like city traffic, short distances to drive, much more turns etc. What i mean is that a car from (just one example) Austria does not last as long as a vehicle from the midwest or so.

I´m always wondering how clean and almost mint some cars with almost 200k on the clock are, if i put this mileage on in my home town or country, there´ll be much more wear on the whole vehicle...

 

[neon98rt]

i saw a white lebaron on ebay with 35k on it. It went for 4500 dollars. If it was local i would have bought it. Even on that car i bet i would have to change parts that would wear out due to age.
I think i spent 3000 on my car.
I have new front hubs and 4 new brake calipers in a box that are going on next.

I still find it cheaper than paying 350 a month for a jeep wrangler that would be worth a tenth of what i paid for it by the time it was paid off.

The best and one of the first things i changed was the fuel injectors. It use to drip down and starting was hard.

 

[Musikmann]

I have over 185,000 on my 3.0 1994 Acclaim. I have done a water pump, fuel pump, alternator, radiator and valve cover gaskets. Changed the ATF every 30,000 and oil every 3000 using Pennzoil 10W30. The engine and transmission seems as strong as the day I bought it new. I fully expect to see 250,000 miles and maybe more.

 

[neon98rt]

is the water pump and timing belt hard to do as in . is there much room to work? would lowering the engine be a quicker way to do it?

 

[John Wood]

is the water pump and timing belt hard to do as in . is there much room to work? would lowering the engine be a quicker way to do it?

On a 3.0 transverse engine, it can be a nuisance. You have to support the engine, remove the passenger side engine mount and possibly raise and lower the engine a small bit to get the bolts holding the front plate out. Those bolts are different lengths, so make sure they go back in the same holes. I just punch some holes in the bottom of a cardboard box to match the front plate and shove the bolts into the holes in the box. That way I never mix them up. Also, you have to unbolt the power steering pump and AC compressor. There is always one difficult bolt to get to below the T-Stat housing area and a phillips head screw on the back of the water pump housing that is often frozen.

It is really a significant amount of labor in a tight working area.

 

[Kevin1990]

I´ve to say on my Voyager, the job was OK, i got more room sideways than on my Saratoga. But the only thing is, that the Minivan´s engine sits a little bit deeper inside, so some bolts are easier to reach through the side / passenger´s side wheel.

And there´s a little pipe extension from the water pipe that runs between the cylinder heads, which you may have to remove or bend a bit so you can get the new water pump in there....pretty tricky, but OK.

 

[rj-]

My '94 Shadow ES is over 196,000 right now.

Water pump was the major issue. That plaus all belts got replaced in 2001. Not long after I got him.

I did have to replace the fuel pump 2 yrs ago. I did the gas tank when I did the pump.

I got a brand new radiator for the car up stairs in my barn. Laziness is why it's still in the box.

 

[Kevin1990]

My '94 Shadow ES is over 196,000 right now.

Water pump was the major issue. That plaus all belts got replaced in 2001. Not long after I got him.

I did have to replace the fuel pump 2 yrs ago. I did the gas tank when I did the pump.

I got a brand new radiator for the car up stairs in my barn. Laziness is why it's still in the box.

Well that´s just fine!

I also had to replace the fuel pump, arround 185k KM (not miles), the radiator is gone too, but doesn´t leak, i also replace it while re - gasketing the Mitsu this summer.

 

[B10alia]

Remember that wear parts are wear parts, even if they're not a frequent replacement item. After about 100k (miles, which is right about what you're coming up to, I figure), things like shocks, struts, brake rotors, wheel bearings, etc are reaching the end of their service life. Say you put $400 in the car for a full suspension. A suspension is a job you only have to do every 10 years or so, so you're talking $40 a year, which is FAR less than the monthly cable bill at my house. Really, the only thing in my book that condemns a car is severe structural rust, with strong second going to engine and transmission failure. Even in case of powertrain failure, I would carefully consider the options. 300 klicks is about 150k miles, which is still relatively young for a car, even under severe service. You'll need to replace suspension parts more often and need to change the oil more often, but that's something that will be true for ANY car. All buying a new car does is "reset" the date when the job has to be done. A new shock is a new shock, regardless if it's under a 1990 or a 2013. If your driving is killing the shocks in 75k, say, it's going to kill any shock in 75k.

 

[Kevin1990]

Nicely said!!

I just put 200 000 KM on my Saratoga, almost 125 000 miles.

Already replaced all wheel beerings, front shocks (rear ones are also dead now), drivers side driveshaft, steering gear and a lot of small parts etc.
Massive rust is the only thing, which keeps me away from buying any vehicle....

My Saratoga is almost rust free, Body 100 %, just some small spots on the rear underbody panels. THATS why i´m fixing what should be fixed and put as many miles / KM on it as it could take. Transmission is the first, oil pump´s noisy since 60 000 KM, still running. I´ll overhaul the engine (cause of oil burning) and the trans in the next couple of weeks. Parts are already stored. But i have to say, i´m definatly no fan of ATF+4 at all, may works on a newer or overhauled Ultradrive, but not in an unopended or old one.

I´ve been driven a 1st Gen. Minivan, running on Dexron III since almost 100 000 KM, perfect shift quality, no problems or excessive wear. But that´s another thing...


I just want to read some notes of high mileage 3.0 Mitsu´s, main bearings, cam´s, crankshaft etc.

 

[B10alia]

A well-maintained engine should not need mains or cam bearings at 125k. Replacing the mains also entails removing and miking the crank, and while you have the engine open and the crank out, you'd be insane not to Plastigauge the big ends and mains, and since you're going THAT far you might as well pull the pistons and check the bores and rings, and deglaze the bores... you can see how this turned into an engine rebuild that it doesn't really seem your engine needs, and a rebuild is something you really need to do with the engine out and in a relatively clean place.
It seems to me that really the worst problems with the 6G72 were valve seals. I wonder sometimes if the 24V DOHC twin-turbo version of this engine had similar problems, or if it was just limited to Chrysler engines. Unfortunately, valve guide seals require removing both cylinder heads which will probably be very difficult in the vehicle (I have never worked on a 3.0, so I don't know for sure, but I have seen the engine compartments of a couple 3.0 AA's, and it does not look like a fun place to have to work). I do know that the head on my 2.5 is heavy enough to basically require two people to get it on the engine properly. Valve guide seals are more of an annoyance than anything else; they really only cause oil consumption.
I'm curious about your choice of 5W-50... why so heavy?
Having heard the horror stories about the use of non-ATF+4 in the A604, I wouldn't recommend straying from that spec. It's superior to D/MIII and is a fully synthetic fluid by definition.
I don't think your engine needs most of the stuff you're talking about. It's not really that old; you're talking about seals that usually last well over 200k. If you've done a head gasket in the car, you can do the valve guide seals without pulling the engine, but I'm looking at my FSM and I'm not so sure that I would want to replace some of these seals, mainly the crank seals, in the car. It's probably doable, but it looks like a headache. In fact, the manual seems to assume that the engine is out.

 

[Kevin1990]

Well, that´s what i was thinking about too. I just will "re - gasket" the engine, no bearings or any hardware. Of course, valve seals, head gasket, cam seals etc....but nothing more.
I run 10W 40 most of the time (Shell or Valvoline MaxLife), i tried a 5W 50 cause of the lifters, no change, so 10W 40 should be fine. AND, a lot of mountain driving here, so you´ll get a much higher oil temperature than in summer city traffic.

Of course, ATF+4 is the only proven choice for the A604, but i guess i just "washed out" the maybe 20 years old dirt of some important areas inside the trans....pressure is OK, TCC works fine, but shift quality isn´t good after 500 KMM of driving. Of course, still learning...but i just say, Dexron III works (or feels....) better to me in the unopened units.

 

[B10alia]

The conception that a transmission works better when it's full of gunk, and that changing the transmission fluid will make things worse always baffles me. I've seen it several times on here. Automatic transmissions are the products of years and millions of dollars of research, engineering and development. If the unit worked better gunked up, the transmission would be "gunked up" from the factory by changing tolerances inside. I agree with you that the TCM is probably re-learning in your case, though. As for proven fluids, D/MIII has been proven to destroy the A604. I would advise using whatever oil weight the factory advises. There are high mileage oils with extra conditioners if leakage is a concern.