Premium Gas For 2000 & 2001 Chrysler 300M's?

89 octane is called for.

It will run on premium if your willing to pay for it.

In the NorthEast 87 is regular, 89 is Mid Grade

What bought the Concordes for the same year? Require the same 89? I'm trying to replace my '95 Concorde (that I feed 87 to with no problems) and I'd just as soon have an LXi than the 300M. There's a plain 2000 Concorde (don't know if it's an LX, LXi or simply a "Concorde") at an auction I plan to attend Saturday.Do they have different engines than the 300M? Bottom line, does a

2000 Concorde run on 87 with no adjustment?

I believe Chrysler recommends the midgrade gas for *all* of the 2nd generation LH cars - most likely an internal design requirement set by the marketing people - not a bad idea.

Avoid the 2.7 liter (comes in some Concordes and Intrepids but not the

300M or LHS). They have been known to severely sludge and self-destruct at relatively low mileage (60-80k miles). I'm over 100k miles on my '99 Concorde with the 2.7L with no problems, but I drive 80 miles a day round trip and have taken special precautions to prevent sludging. Stick with the 3.2 or 3.5L unless you get an especially good deal on a 2.7, check out the engine's condition, are willing to take a little more risk, and are willing to do some preventative steps to prevent sludging (if it's not already too late).

Be aware that the 2.7 also has a timing chain - not a belt (a plus) but is interference (a minus if the chain ever lets loose). The 3.2 has a belt driven cam and is interference (a big minus when combined with a belt, though belts have gotten very reliable over the last several years). 3.5 is belt (a minus in my book) but non-interference (a plus).

IMO...

Bill Putney (to reply by e-mail, replace the last letter of the alphabet in my address with "x")

The 300M will run on the cheap stuff but you sacrifice some performance.

might say

Are you sure the new 3.5 is non-interferernce? References vary. The old one was but it has been disputed for the new one.

line, does a

self-destruct

sludging

87 is regular, 89 is midgrade.

Even with knock sensors and computer controls? I don't think so.

Bill Putney (to reply by e-mail, replace the last letter of the alphabet in my address with "x")

I believe Chrysler V6 engines are all designed to run on 87 octane fuel. The

300M Special uses 89 octane to get its extra 5 hp, but will run on 87 (just won't give the 5 extra hp).

I don't know from expererience - only going by the Gates Guide, so I could be wrong.

Bill Putney (to reply by e-mail, replace the last letter of the alphabet in my address with "x")

Never heard that one before. Why? Do you have an independent reference for this? Using premium is a waste of money if it isn't needed, but I've never heard of it causing harm ... other than to your wallet.

Matt

I believe the owner's manual recommends against premium for the regular 300M engine but haven't looked lately and my memory isn't what it used to be. I stick to the recommended mid grade which it definitely states in the manual. That much I remember.

reference

Been feeding my '00 M with 87 octane pretty much since day 1 (which is

4 years 2 weeks now). That even includes the time-frame when Shell Canada was supplying bad gas that was gumming up parts of the fuel system that Chrysler cars were for some reason more succeptible to (and yes I get about half my gas from Shell stations).

While on the topic of the M, what are other owners doing about

- coolant replacement

- brake fluid replacement

- battery

- timing belt

- spark plug replacement

- fuel injector maintanence

- differential fluid

- power steering fluid

- anything else?

Aside from the differential and PS fluid which was changed this past summer, everything else on the car is original. K&N air filter gets cleaned and oiled about twice a year, and oil+filter gets changed 3 times per year.

I'm wondering what others are doing about plug replacement and injector cleaning. Anyone throw a bottle of injector cleaner in the tank (good idea, won't hurt or help, or bad idea) ?

Anyone have to get a new battery for their M yet? If so, what year - and how many miles?

Depends on where you are. What you said is generally true at most altitudes. At higher altitudes, 85 is often regular, and 87 is midgrade. (Detonation is less of a problem when the air is less dense (because there is less air to compress)).

Premium hurts nothing but your pocketbook.

You need to visit the 300M Enthusiasts club - $15, access to FSM microfiche parts catalogs, and other stuff online.

Their forums (300M ezBoard) are broken down into very specific categories, such as, one on changing spark plugs, another on tires and wheels, one on brakes, a forum on nothing but black trim and wetherstripping, transmission, etc, etc., etc.

You didn't mention changing the tranny fluid and filter - you definitely need to do that. 60 to 80k mile intervals should work well.

P.S. fluid would be flushed and ATF+4 used for refill (Chrysler dealers can't get the branded P.S. fluid because Chryler says to sub. ATF+4).

Coolant: Chrysler antifreeze or Zerex G05 (the aftermarket brand same thing) - supposed to not have certain issues that the orange stuff (Prestone Extended Life?/DexCool?) has.

I have seen not a single post on injector problems, so they apparently are very problem free, but I throw some Techron? or Marvel Mystery Oil in the gas every once in a while as routine/preventative maintenance.

(BTW - mine's a Concorde not an M, but same car mechanically, except for my 2.7L engine).

Bill Putney (to reply by e-mail, replace the last letter of the alphabet in my address with "x")

Oops - that's $15 to join and have access to the info. and other bene's (Club decal, etc.).

The forums are open to the public. Great bunch of guys.

One guy has broken into the 14's with simple mods.

Bill Putney (to reply by e-mail, replace the last letter of the alphabet in my address with "x")