A friend is thinking about getting a new 300, most likely with the 3.5
engine. From reading magazines over the years, I know that this engine
is "nothing special." At least is doesn't win the awards and high
praise that certain Honda and Nissan bent sixes receive. My friend
doesn't care much about having the world's best V-6, but is concerned
about service life and general reliability. How is the 3.5 in this
regard? Are there any specific issues, like valve gear, bearings,
accessories, sludging, or anything else of significance?
TIA for any info from those who work on, or own high mileage 3.5's.
replying to General Schvantzkoph, KC wrote:
I have a 99 , 300 m with 159,650 miles on it. Have had some issues with other
area's in this car. First two years it was flat beded in five times . Spent more
time at the dealership being repaired in the first two years! Numerous other
issues too. Last week driving at 55mph I started hearing this terrible noise
coming from under the hood . Took it to a local repair shop and found out it has
spun a bearing and atleast one if not more pistons are hitting the cylinder
head. Any used engine put back in it would be a big gamble and probably throwing
money away ! Still has other issues that needed to be looked at and repaired.
Definitely not very dependable !
Wow, 159,000 miles and it finally wore out.
Did you use synthetic oil or regular oil? Did you do oil changes on
Just trying to anticipate what to look forward to since I am the
original owner of a 2000 3ooM with 42,000 miles.
Um, Steve -
Did you notice that "KC" started this thread on Saturday- by replying to
a post made in 2004?
Steve Stone wrote:
I own a 2000 Chrysler 300m - bought it new back in November 1999.
It has 133k miles on it. In 2012 or 2013 I took it to a dealer to
replace the timing belt - because it was the original belt and it was
10+ years old and if that belt breaks then the engine is toast.
Otherwise the engine was in perfect shape. I had the timing belt idler
pulley, the water pump and a few seals changed as part of the same job
because why not - since all the labor cost was already covered to get to
the timing belt.
The engine is otherwise trouble free in 16 years. Had to replace 1
spark-plug ignition coil. Had to replace the front exhaust couplers
(the semi-flexible joint after the cat convertors) and the exhaust
resonator (where the 2 exhaust pipes join into a single pipe, sort of
looks like a muffler). Otherwise all original exhaust components remain
in place, including the muffler (bottom surface is peppered with holes
but they don't seem to make a difference).
Just make sure you change the gear oil (differential fluid) every once
in while. The 300m transaxle has it's own oil sump, takes a liter of
SAE 90 oil (don't use synthetic!). Other cars lubricate the transaxle
with transmission fluid - which is lame.
Never had anything done with the transmission. Even tranny oil is
Car gets 28 to 30 mpg on the highway at 65 - 70 mph.
Never had anything done to fuel system (original injectors, original
fuel pump, original fuel filter, etc).
Suspension is where the focus is on the 300m (and probably all LH-body
cars). I've replaced all 4 struts (with complete replacements, known as
"quick-strut" units, fully assembled). Unless you drive on very flat
and well-maintained roads you're going to have to replace the front sway
bar bushings every 4 years or live with a knocking sound from the front
I've replaced all 4 wheel bearings (because why not if the price is
right). Have replaced the sway bar links once or twice. I've replaced
one of the lower control arms and torsion strut rod and bushings, going
to do the same on the other side soon. Still using original outer tie
rods but I'm going to be replacing the inner tie rod bushings (because
these wear out and I assume mine has). Probably buy the entire rods and
ends because they're cheap enough (Rock Auto).
One stupid problem I have is that over the past 3 years I've been
getting less and less heat out of the heater. Heater core getting
plugged up seems to be a chronic problem in LH cars. I'll try to flush
the shit out of it when I work on the inner tie rod bushings (need to
remove the hood and cross-piece thing to do that, and that gives me
access to heater hoses at the firewall).
Other than the timing belt, I do all the work on this car myself.
Door speakers wear out (cone separates from frame) and I've used epoxy
to repair it, but it doesn't last.
I bought a set of after-market head lights from china or singapore a few
months ago (Eagle Eyes, from ebay) for $80 (came with light bulbs) and
wow, crystal clear head lights make the car look new again!
So yes, the 3.5 engine is fantastic. I should have bought another
chrysler 300m back in 2004 and just kept it in a box for when my 2000
car finally wears out. I do not like anything that anyone's making now,
and I've always hated the bloated, boxy and heavy 300c that Chrysler
replaced the 300m with in 2005.
I don't claim to be an expert and this is just my opinion.
I've been in the automotive industry for the last 30 plus
years and learn something new every day.
I've had a fair amount of experience with the chrysler 2.7 ,
3.2 and 3.5 in their LH body cars.
I had a 2.7L , my personal car , seize up at an idle with no warning.
These are known for consuming coolant and it was my fault for not
fixing that problem , which led to the engine failure.
Back to the original thread topic . It seems as if Chrysler was after
some additional fuel mileage and HP when they built the 2nd gen.
3.5L engines. I have a 183,000 mile 3.5 that I put a set of rod brgs
in at 172,000. I had just purchased the vehicle and noticed an ever
so slight knock on start up only. After pulling the pan and looking at
the bearings , only the upper half was just starting to see copper, the
bottom half looked good for the miles.
If you look at the bearing width vs. the crank journal and conn. rod
width , Chrysler could have very easily used a bearing .100 wider to
help with the load carrying capacity, but that causes more rotating
friction. I'd rather give up 1 mpg than have to think about loosing
the bottom end.
I had nothing to loose but my time and the cost of a set of rod bearings
, so I polished it up and put it back together.
Now just a little more rambling,,,,,
- People think their doing a good job by going to a quick lube every
3000 miles . The oil they use it the cheapest crap they can buy !!
I'm not here to sell oil but you get what you pay for " most of the
time" do your homework , even some of the top advertised synthetics
aren't that great.
- Run a premium oil filter
- And from my own experience , when you have " ANY " amount of
coolant consumption , address it immediately.
I honestly believe because they have a weaker than average bottom
end that all of the above is super critical.
Again , Just my humble opinion and to end on a positive note , if I
didn't enjoy driving my car and I really do , I'd never put this kind of
work into it.
replying to Steve Stone, Richard wrote:
Quite agree Steve, spot on advice re oil, and the weak bottom end....a basic
engineering design fault, to not provide a shade more bearing width, and the
extra drag too minimal to shave even 1 mpg off the standard. It is staggering to
see a team of Chrysler design engineers so incompetent as to provide an engine
that is on a par with a 1960,s engine....narrow bearings and too high a load to
cope...but they lasted longer then even with the rubbish oils of that era. I
have a very dim view of today,s engineers, where even Lexus get it wrong...too
many smart letter after a name , and no spanner experience makes a crap
Those same magazines who are telling you that the 3.5L is nothing special
are the ones that were singing its praises 3 years ago. If you happened to
read that opinion in Automobile magazine, I would take it with a very large
grain of salt, as I do with *most* of what they say.
The 3.5L is a durable, well-designed engine. If it has not undergone major
changes, it is the same one that was placed in 2nd generation LH cars
beginning in 1999 for the 300M, and as a premium engine in the other LH
cars. Although all engines can sometimes fail prematurely, the 3.5L doesn't
have a track record of doing so. It is equipped with a coil-over-sparkplug
ignition system that is very reliable and essentially maintenance-free.
For its displacement, it is a very powerful engine, and it yields more than
1HP/cubic inch, which is something that the magazine guys normally get all
excited over. Unfortunately, it is overwhelmed by the great bulk of a
Pacifica, an extremely overweight vehicle, as many engines of larger
displacement also would be. My understanding is that it performs quite
acceptably in a 300.
Personally, I have a 3.2L engine, which is a close cousin to the 3.5L,
sharing many aspects of the design. It has been a remarkably trouble free
engine, smooth and powerful for its size, and reasonably economical. Mine
has 95,000 miles on it, and has no odd noises, leaks of any kind, or
performance/starting issues. So far, I've replaced one idler pulley that
got a bit noisy around 80,000 miles. I would expect similar service from a
There was an earlier version of the 3.5L placed in the 1st generation LH
cars. It was the premium engine in that application as well. People have
driven that version well past 200,000 miles with only normal maintenance.
However, the design was changed radically for the second generation cars, so
direct comparisons aren't necessarily valid.
Can you elaborate on the "radical" design changes between the 1st and 2nd
generation LH 3.5L? Just curious. I think I read something about 1st
generation being non-interference, and that was changed in the 2nd
There's a pretty good discussion of the 2nd-gen 3.5L on AllPar's site at
The 1st-gen is covered at http://www.allpar.com/mopar/33.html , scroll down
to the section entitled "The 3.5 liter engine according to Chrysler"
The biggest change is that the first-genration had a cast nickel/iron
block, the second gen has an aluminum block with nickel/iron liners. The
second gen also has coil-on-plug ignition, and is apparently now an
interference engine due to changes either in the combustion chamber or
the piston compression height. However, very little (essentially
nothing) changed with the rotating assembly- still a forged steel crank,
nice long rods swinging short "slipper" pistons with a relatively low
bob-weight (some other makers stick with taller pistons and shorten the
RODS which leads to greater side-loading on the cylinder walls and
higher stresses in the rod itself), cross-bolted mains (I believe with a
full block girdle in the aluminum version, not necessary in the iron
version). All-in-all its one HELL of a fine engine. You don't hear much
about it because, like the 318, 383, 440, and slant-six before it, it
just goes out and does its job for hundreds of thousands of miles
without fancy advertizing.
As an owner of a Pacifica since last August 29 (and an occasional driver as it
is my wife's vehicle) I can tell you that in normal, daily Los Angeles driving
situations (including merging onto freeways at 65+ mph) the Pacifica is not
overwhelmed but performs quite well. Only once have I found it overwhelmed and
that was when I had to stop for a red light at the bottom of a steep hill and
then proceed up the hill when the light changed. As we are both #1 lane (fast
lane) drivers we have no complaints about the performance. I have read some
accounts of reviewers that say the performance of the 3.5 in the 300 and Magnum
is quite respectable.
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