180k Mile Maintenance Question

Status
Not open for further replies.
Joined
May 9, 2005
Messages
1,073
Location
Central IN
Hey guys, I've got an '04 Chevy Colorado 4x4 with the 3.5L Inline 5-cylinder engine. It's going to turn 180k here in the next couple months so I'm trying to come up with a plan of attack for service. I've got a couple questions:

1) Do coil packs need to be replaced at a certain interval or do you just replace them as they die? I had to replace one last summer when it went out so I thought that maybe I should just replace the rest of them with this next round of service. I'll be replacing spark plugs so I'll already be removing them anyway.

2) At 120k miles (May of 2012) I replaced the factory 4x4 fluids with Mobil1 75w90 (diffs) and Redline MTL (xfer case). These fluids therefore have seen 60k miles and nearly 5 years of service on them. Should I go ahead and dump/re-fill these fluids or go farther and if so, how much farther would you recommend? My commute is mostly highway type driving, about 12k per year at this point. I'm not interested in UOA's on these fluids, fyi. If I dump/refill them, I'll stick with the respective fluids unless there's something better I should use.

Any help would be greatly appreciated.
 
i would change the fluids at the interval recommended for severe service in the owners manual. or every 30k miles if no manual
 
I would not replace any working coil packs. I've still got the originals on my 1995 Escort at 238K miles. If anything, the originals, even at high mileage, are probably better than a lot of aftermarket coils.
 
I've maintained older vehicles for the last 45 years and I have found it unnecessary to change coils and or the fluids you are talking about. I would wait at least another two years.
 
I agree with leaving the original coils in there. Don't replace them if they aren't broken, it would be a shame to replace working parts with potentially lesser quality aftermarkets and have issues.

As far as the fluids, it depends on how long you plan on keeping the truck. The most wear on those items occurs during break-in. We just changed the differential fluids on my buddy's Cherokee two weekends ago. The fluid was Mobil 1 gear oil and it had been in there for 60k miles. It looked exactly the same as it went in, maybe a tad bit darker. It could've easily been left in for longer, and his Jeep has 190k on it.
 
Originally Posted By: zzyzzx
I would not replace any working coil packs. I've still got the originals on my 1995 Escort at 238K miles. If anything, the originals, even at high mileage, are probably better than a lot of aftermarket coils.


You sure that car has coil packs and not one coil???
 
I have a fwd six cylinder car and regret not changing all at one time. You have to determine which coil is at issue, and the codes are sometimes wrong. If one goes, they are all suspect. In my car, replacement requires some disassembly. Agree with replacing at OEM quality level, but smart money is to replace them all in one shot.
 
Originally Posted By: TomYoung
Originally Posted By: zzyzzx
I would not replace any working coil packs. I've still got the originals on my 1995 Escort at 238K miles. If anything, the originals, even at high mileage, are probably better than a lot of aftermarket coils.


You sure that car has coil packs and not one coil???


True, it's one pack with 2 coils in it, but the same principle applies.
 
Originally Posted By: zzyzzx
Originally Posted By: TomYoung
Originally Posted By: zzyzzx
I would not replace any working coil packs. I've still got the originals on my 1995 Escort at 238K miles. If anything, the originals, even at high mileage, are probably better than a lot of aftermarket coils.


You sure that car has coil packs and not one coil???

the
True, it's one pack with 2 coils in it, but the same principle applies.


No, it is a much more old-school technology well-removed from the level of heat that on-plug coil packs experience. If I were driving a 1995 Escort, I would drive that coil pack until it fails, which might well be never.
 
I personally wouldn't change the other coils until they give up. Gearbox oils, changing them with 60K on them isn't a total waste but outside of a weak unit that needs excellent maintenance just to stay in one piece I'd wait until 200K. Unless you've done it since that 120K service I'd address the cooling system instead - a flush and clean with Cascade powdered dish detergent is what I've done. Flush all antifreeze out with water (I just ran a hose in the radiator neck, with engine running/drain cock open until it was clear) then close it up with 1/2 pound? of Cascade powdered dish detergent, take a 10-15 minute drive then flush again immediately. Let it cool, drain all the water you can, then refill with your preferred mix or distilled water/concentrate. Also might be time to replace the PCV valve, clean the throttle body, etc. if you haven't already.
 
You keep a coil or two in the trunk of the car along with the necessary tool (aka hex key etc) if the coil dies you on the road.
 
Thanks for all the replies and input guys.

I'll leave the coil packs alone and just replace the plugs as I was already planning (NGK Iridium's).

I was also planning to do a coolant flush, but never heard of using Cascade. After doing a little Google'ing, I may give that a shot. It's been 7 years and 90k miles since I had the dex-cool filled system flushed at a quick-lube place with Prestone products.

Thanks again guys!
 
Status
Not open for further replies.
Back
Top