Hey guys, My 98 3/4 ton has problems. Main one is overheating. Its the gas 5.9 auto. I just replaced freeze plugs, thermostat,.I cannot hear the waterpump bearing going out, or notice any weeping, so I cancelled that idea..Here is what she is doing. Starts and runs fine at idle. When she is getting up to temp, the heat seems to get hot and the gauge is working good, but when I start to ramp it up, the gauge starts to climb, and cold air blows out inside cab. Then I can give her a couple of good romps, the gauge goes back down, wahla heat again. I even took it for a test drive, gauge climbed to the red zone, then back down again. brought her home, same thing. That is the heat problem.

Other problem I got is when I kick her into passing gear, she bogs right down, no stumble, just acts like it stops picking up speed. Needless to say I cannot pass anyone. I have noticed the gauges going wacky at times, when this happens, the tach and speedo fluctuate, all this while kicking into passing gear.

I need help on the first issue worst, cause I cant drive it. The second issue has been ongoing before the freeze plugs went.

I am racking my brain, trying to figure these two problems out. I have no shops around here that Want to touch my Beast! so I'm on my own.

Please help!!

 

Does your cruise control work? Could be a case of wild vents. A search should yield several threads regarding the subject...

 

the no-heat is an air pocket in the cooling system at the heater core. if this is a new problem, you need to bleed out the air. either park with front end up high and run the engine for awhile with radiator cap off. or - get a flush adapter with the screw on garden hose adapter and install it in either one of the heater hoses close to the heater core. use the hose cap as a bleeder valve. it also sounds like your coolant level is low.

if this is an old problem that's chronically overheating, you need to do a compression check to test for the unspeakable - head gasket or cracked head. if that's ok, then check radiator.

 

Im with dhvaughan. I think you have an air pocket somewhere, that isnt working itself out... as he said... most likely in the heater core. I dont know what you have already done, but I would pull the radiator cap while its cold, start it and let it run for a while, until your heater is blowing hot. Be sure to keep checking on your coolant fluid level, as you dont want to run low. Make sure your heater is set to full heat. Once your thermostat opens up, it should get a good flow of coolant running through your heater core.

 

That flavor of overheating is due to being low on coolant. Burp the system as suggested above.

 

ok, i am burping right now, i have already put 4 full jugs of antifreeze in, working on slowly pouring fifth one to keep full. So how long does it usually take to complete process? isn't having the radiatior cap off, letting air into the system? i got lotts of burps coming out.
thanks again guys. after I fix this hopefully, we'll have to move on to other problem..ha ha

 

Sounds like a blown head gasket/ cracked head. The truck shouldn't take that many jugs, 2 the most. If you have it running with the rad cap off and the water is bubbling/ burping rapidly then you have a blown head/ gasket and might be leaking through your exhaust. check you CEL light & spark plugs. i assumed that you checked the oil for water in the system.

 

4 gallons is what the whole system takes. So, he was either real low or something is leaking. LOL

 

Really? These trucks hold approximately 5 gallons (that's 5 jugs) of coolant. He drained block (to replace freeze plugs) so his was totally empty.

 

After replacing All the FREEZE PLUGS I put 4 gallons in the truck.. not knowing exactly how many Gallons of antifreeze To put in..

I just added another gallon (making it 5 Gallons total, none leaking) and with its burping (not much anymore, but still burping) it spits out antifreeze.. I dont want to waist antifreeze it gets pretty $$, Dont want to Dilute with water cause then could cause problems.

Still not much heat (blower works Like it always has)... When I rev her then i get heat, for short time??
Heats been on HIGH for 45 min and truck been running for about same.. Her temp is about 200-220.. then rev her up I get heat But NOT HOT. temp goes down. Once the Temp goes down Back to No heat?? One heater hose warm (not HOT ) other cold.

Everything has been checked out.