Deltas are good, time for coolant change. Do a full flush?

[Foxbodyford]

Have had the vehicle for a few thousand. Deltas are about 6*. I know it should have been done already, but don't know if it has. I'm @ 90K miles now on my 6L.

My question is I've seen people who do a flush and afterward their deltas are higher than they were. I know if I do a flush and it clogs my oil cooler I'm spending money that I don't have budgeted at this time. I am adding a coolant filter and plan on swapping the coolant and cleaning the degas bottle. I was planning on doing a full system flush, and switching to CAT ELC. I have decided I'd rather keep the Ford gold and change the coolant ever 30K miles or so. After a oil cooler swap or bullet proofing I'll likely switch.

So given I'm sticking with Ford gold, have good deltas, am adding a coolant filter kit, SHOULD I do a full flush with the restore and vc9 (not sure if thats the right name) or just drain, and refill?

[seeemmiss]

I have the same question. Hope some knowing soul will answer.

[colo_dually]

If you can't afford to clog that cooler right now, I would only do a drain and refill. Its not the best answer, but it will keep that oil cooler from clogging up from the debris. Realize your system will need a real flush sooner than you would think, but you should be able to hold it off until its better for the budget.

My dealership did my HG's under warranty, after the EGR cooler failed. Their procedure is the VC9 flush after the Oil Cooler was replaced (this is due to worse case of oil cooler rupture), my deltas leaving the shop that day were 8* on a new oil cooler.

It won't be done like that again, and I always recommend waiting on any flush until you are ready to do it right and include an oil cooler rebuild/replacement (or aftermarket upgrade) at the same time.

[jimmyv13]

I am in the same situation. My delta is good, 6-7, and I feel I should get the gold out of there. I was told that as long as my delta was good, a thorough flush with DI water would be sufficient then swap to ELC.

[L&B]

Originally Posted by jimmyv13

I am in the same situation. My delta is good, 6-7, and I feel I should get the gold out of there. I was told that as long as my delta was good, a thorough flush with DI water would be sufficient then swap to ELC.

Mine got new coolers under warranty. Once we were sure that it didn't need to go back for any reason I pulled the starter, block drains, lower rad. hose, and thermostat. Installed Fumoto valves in the block with about 2' of some cheap hose, put the starter back on etc. Flushed it with water only with idling/mild driving for about 5-10 minutes to help circulate coolant between flushes. It took a bit over 20 gal. until it was coming out clear. Replaced the thermostat and refilled with Delo ELC. That was about 5k miles ago. Deltas have actually dropped a degree or two and I'm very happy with the result.

In my opinion, both the need for chemical flushing agents as well as their efficacy has been exaggerated to some extent. They do have a function, but are far from essential in most cases. I personally would rather see someone skip the chemical flushing agents and run an ELC than to keep G-05 coolants in a system over fear that the extended flush protocol will plug their cooler.

[harlo]

Seems to be a gamble. When I flushed my truck (both chemicals) I went from 8 degree to a 10 degree delta. Its been over a year now and still at 10 degrees. In specs but not perfect.

[roadrunner]

My suggestion is to skip the VC-9/Restore+, do the restore flush to remove 90,000 mi. of build-up.
When you're finished do the reverse flush to clear any debris from the oil cooler and add coolant.

In my personal opinion I think the trucks that have had the coolant issues had underlying coolant system issues, either a small head gasket leak or egr cooler leak caused the coolant debris. That would explain why some trucks are trouble-free and some are trouble-prone.

[Foxbodyford]

Looking back over my Oasis report, the coolant was changed once. Glad its not as old as I though.

I am going to add a coolant filter, drain coolant, do a brief and minor flush with distilled water just long enough get the thermostat open, then clean the coolant bottle, and then I'm doing a refill. I'll check the filter after a few thousand miles and assess it then.

I'd rather flush the system a few times little by little than to try and clear it all out at one time and risk clogging my cooler. My reasoning is it this. It didn't get there over night, its not clogged now, why not remove it little by little obviously at a faster rate than it was added (it being broken down coolant)

Its not like I'm pouring more filter clogging stuff immediately. My understanding is the coolant breaks down little by little and by draining and refilling the system a few times with fresh coolant I can delay having to do an oil cooler/egr update.