99' 4.0 coolant

what is the best coolant to use for my 99' 4.0 inline six? any suggestions would be appreciated

I have a preference for OEM Mopar coolant, it may be no different from standard prestone BUT it may be manufactured to specific requirements that may cost more money hence the makeup might be different from store bought over the counter.
Over the time I have been here I have read posts from members and others that have used other brands, some with OK results but a few with bad results. Me, I'm at 180,000+ miles, I used to drive by the jeep dealer daily so it was no big deal to pickup the coolant there. In the wifes Oldsmobile I used standard prestone, her water pump failed, engine overheated badly and warped the heads, ended up springing for a new motor. Last time I bought OEM from the dealer the price difference was less then $1.50 per gallon.

I agree with RichP- when I used Prestone (changed every other year), the best I got was 6 years out of a radiator. Since I switched to using Mopar, mixed 50:50 with distilled water, I got 13 years out of my 1990 2-core XJ rad- and then replaced it due to a seam leak, with the inside still looking good. The Chrysler dealer stuff is better than anything else I have tried, but you still have to change it. 4xBob

I'm using that 5-year stuff in my '98. Don't rem the name, but is at Wal-Mart. Not to be confused with Dex Cool..... So far after 6 months of use looks perfect. Distilled water must be used- to bad it is not de-ionized too. That would also help things. Do sorta like that pre-mixed coolant cause has used deionized and distilled water for the mix.

What i have seen in engines is that some treat coolant very well. Most Jap engines are very good to the coolant and seems to last almost indefinitely. Other's, like many american engines, hammer the hell out of the stuff. Is mostly a function of materials used in the construction in which the coolant operates i think. My old T/A with the 400 engine nastied up the coolant in 6 months although did not seem to have an effect on anything in particular. My CRX keeps the coolant virtually perfect for years. So far, my Jeep 4.0 seems to be somewhere in between. Two years will be the change interval for that i believe.

There was that write up on installing a filter on the heater hose. I am thinking of doing the same on the upper rad hose. Would like to see if there is any debris in the system, and installing it there would assure nothing entering the top of the rad cores potentially clogging things up. Some have indicated this can be a problem on these 4.0s although i have never seen this as a problem on any radiator i have had apart from any type of vehicle.

thanks for the info, i'll go pick some up at a jeep/chrysler dealer