HowdyMy third post, yee ha. I did my research, made sure I had the correct coolant, followed the procedure and turned the engine on to get vacum to turn heater on. I drained it but when I refilled it, it only took 4 gallons. I was told with refill, it was 5 to 5.5 gallons. Any thoughts? also, some FYI, I had to replace my ball joints, and track bar at 60,000 miles. I put Moogs on so am hoping these will last. MarkFlagstaff, AZ

Ahhh... You got caught... Yes the coolant capacity is 6 gallons. But the problem is that you have a tough time getting the last gallon out unless you put the truck on a steep nose down slope. Then you can drain it out. As for filling it up you got to turn the truck around to aid in air removal so have the truck in a steep up hill slope. I typically see about 5-5.5 gallons doing it this way. As for the heater there is no vacuum control valve like older versions. The heater core is directly plumbed to the block. Some also pull a heater hose at the block to aid in air removal.

thank you for your help but Im not sure I still understand. I flushed the block and it ran clear. If there was old coolant down inside, wouldn't it have flushed out?

I thought you just drained what you could and filled it back up, you never said you flushed it til now. If you flushed it then all the old coolant should be out.

so any ideas why it only took 4 gallons?

Because the the last 1-2 gallons is trapped in the bottom of the block and usually the air trapped in the system takes time to burp out... So like I said you'll get close with 5 gallons... Next time I flush mine out I'll get pics of the way I park my truck for draining...