Well gents, hopefully all bad things come in 3's because I don't know if I can handle a fourth in 2 days.

Here's my perdicament:

Went to the beach today. 2nd time on the beach with the Yank TT300, no real problems the first time, just running a bit hot. This is the first time on the beach with the 6.0. So, I'm cruising along keeping an eye on my engine and tranny temps since it's 105 with heat index. Everything looks OK. Tranny temps about 200, Engine temps about 210 when I get to a nice spot to chill out for a while. After a few minutes at the beach, I decide to check the engine temps to see if she's cooled down any. Stupid me wasn't thinkning about leaving the truck running to keep the coolant circulating and the ECT guage is pegged at 260 with the Check Engine Coolant light on. Turn heater on and can't do too much about it now. After a few hours of swimming and getting a decent burn It's time to grab some grub. Well as soon as I start the truck up, I can tell an immediate difference in the exhaust note. It sounds like she's plugged up.

Onto to the highway and I get this horrible shudder. Pull over and check to make sure she's in 2WD. She is, hubs are unlocked.

After a few miles. I'm suspecting the TC since the shudder is less noticable at higher RPMs. 1800+ RPMs and the shudder is barely noticable. When she shifts into OD or locks up in a lower gear (~1300-1500 RPMs) the truck SHAKES real bad. Almost like a rear u joint at first, but I think it's more centered. The shaking reminded me of when I was low on tranny fluid when I was filling up the tranny after the yank install. Checked the tranny fluid and that's good. I experienced a bit of slipping one time, but that cleared up. I also had a problem with the TC not unlocking, but I can't reprodice that either.

Last but not least, I'm thinking I may have blown a head gasket from the high ECT and muffled exhaust note. I'll check the oil and coolant tomorrow when it's light out.

I'm also continuosly throwing a code. Bank 2 F-trims too lean.

Relevent Mods:
6.0l
Yank TT300
ASM's
160 degree stat
Flex-a-Lite fans
6.0l Radiator
4 WD 4l60e with a Trans-go shift kit
G80
Tuning

I'm thinking a blown head gasket, burned up yank TT300, toasted tranny, and/or maybe even a busted tranny mount or rear end since the truck was bouncing a good bit through the ruts. Hopefully this is concise enough for you all to give me an educated input.

Thanks gents. I hope you all can help me out.

 

has it lost power? how about a slightly melted cat?

 

With that fault, something happened to bank 2 during the overheat. A cyl on bank 2 could have let go and could have leaked coolant into bank 2 exhaust. You would need to do a compression check and/or leak down to verify. The shudder has to do with the yank lock up probably.

 

I wouldn't think you'd have to leave the engine running for a truck with an indicated 210ECT...

That's really messed up though. I don't know what to think of everything. I'm sorry man.

 

Good info all. The cat sounds like a good route to pursue.

Terminator: It doesn't seem like she lost any power, I got on her once to check it out and aside from the hard shifts and shudder, it felt strong. I definately need to get a compression tester.

mudz5.3: With my Bank 2 F-Trims too lean, could this set the truck to safe mode possibly causing the TC lockup problems? Is safe mode even active with TM removed with tuning? Bank 2 is the passenger side?

marc_w: I didn't think so either, but I guess without the water pump circulating, the stagnant coolant absorbed the built up engine heat? I've never seen this happen before, but my ECT temps are usually in the 180 degree range.

Thanks!

 

OBX, if the coolant isn't circulating, yes it will rise in temp, but in a normal situation it will not blow a headgasket or crack a head. If it did then anyone in a hot environment would not have a vehicle. That leads me to think that there was something else wrong that caused it.
As far as the bank 2 fault. I believe bank 2 would be the pass side but not 100% sure. Was the tm removed from the engine too? I am not sure of gm's programming protocalls but on bmw, if it sets a lean fault, it just sets a c/e light until it doesn't see the fault for so many key cycles or the fault is cleared. I don't thik it would put it in a safe mode of some sort but I am not sure either. Another thought would be that the engine got so hot, and the trans lines run through the radiator, thinking that something could have happened there too. Meaning that if the coolant escaped or if it got really hot, then it could have burned the trans fluid but doubtful. What was the coolant level, oil level, and trans fluid levels like? Also look at the condition of the trans fluid. Does it smell burnt? Look dark, more of a brown color?

 

OK.. so you were crusing the beach and your ECT was ~210 then you turned the truck off for a few minutes, cranked it back up and your ECT were at 260?? That dosnt make a lot of sence. You should not get anywhere near that amount of headsoak. The only time mine has gotten that hot was when my fans quit because of a wireing issue. So how were the temps looking on your way home??
I would check all you fluids like has been mentioned already. Look for oil in coolant, coolant in oil and burnt tranny fluid.

 

Well, I think I found the problem! I forgot to mention that I replaced the plug wires the other day. Just got some from the dealer. They were about an 1 1/2" longer, but I thought they fit fine. Guess I was wrong. The wire for the number 4 cylinder ended up burning through. Thank you AS&M!

So , 7 new wires and one old one and she's up and running like before. I'm surprised I didn't see it when I was checking the tranny fluid yesterday. Heck, I almost missed it today, just happened to look down while checking the oil.

 

Why did the low coolant light come on? Glad you got it fixed none the less.

 

Time to finish. I had to cut the last post short due to a fire call.

Mudz5.3: The light came on since the ECT guage was pegged. I think it was just a general "Check Coolant" message, maybe it was "Check Coolant Temp" ?. I hope it was more specific because if it was over heating and someone who didn't know any better and popped the cap of while it was over heating, bad things are bound to happen.

So, I was was basically short one plug wire. Why didn't I get a misfire code on that cylinder instead of the Fuel Trim Bank 2 Too Lean?

Thanks for all the help. I'm off to work on the Jeep!