Radiator and Transmission Problem. NEED HELP 96 Chevy k1500

[Trentman]

This is my first post so far but I'm tired of searching through the Internet for solutions and figured Id make an account. I have a 96 Chevy k1500 200k with a swapped motor 5.7 Vortec that I'm not sure how many miles are on it.

 

I was driving the other day and the truck refused to shift out of second gear. It did a few times but hardly ever. This is the first time that this has happened. It stayed at right around 4-5000 rpms the entire time. About ten minutes from home the temp gauge shot up and ,axed out. I pulled over right away and turned the truck off. Radiator fluid was everywhere. I had buddies come bring me water and follow me home. After getting home I took my radiator off and cleaned it real good. Mind you I just bought this truck off a guy not too long ago. The radiator was full of gunk. I took hoses off and cleaned real good. One has was damn near clogged completely I cleaned it out good and the coolant tank real good.

 

When I start the truck now it leaks like a waterfall out the back of the engine by the passenger side. That is just letting it run without driving it or anything. It leaks coolant out. My question is what would cause my tranny to not wanna shift like that? Do I need a new transmission?? Tranny filter and fluid change??? Or rebuild?? Also do I have a head gasket blown that is leaking coolant real bad??? It's hard to see up in there but that's kinda what it looks like. It leaks real bad. Or could it be a bad water pump??? I'm not a mechanic or even close but I like doing just about anything I can on my own. I have a 20x40 pool barn I do my work in. Any responses would help. I need the truck to haul wood to heat my home. Anything will be useful. Like I said this is my first post on a forum im very new to this, but I could really use some help. Iv checked my hoses and radiator they are fine besides the gunk which I cleaned out but the entire system could probably use multiple flushes. Thanks for any help guys

[Trentman]

Does anybody know of anything please?

[txab]

As for the trans, imo, best to let a trans take a look at it. Your water leak at the rear maybe a heater hose line/fitting. Seems like that model had problems in that area iirc.

[Trentman]

Could be that I didn't have neutral saftey switch hooked up but I have no idea. I'm pretty sure my head gasket is whats leaking

[barry G]

dig right in, see whats going on in there.

 

the vortec is not known for blowing the right rear, that is typically lopsided tbi.

Vortec monitors two banks separate.

you must have really roasted a vortec if that is the prioblem.

 

may go for a third engine.

 

that happens to all chevys.

[Friz2]

If your head gasket is that far gone, it should run like crap due to filling the cylinder with water, I would think. How does the oil look? Milky, cloudy? Maybe a freeze plug blew out as the motor was boiling, or it rusted away. Considering what your radiator looked like, a rusted freeze plug is likely.

As far as the tranny, the radiator has a tranny cooler in it. If your radiator is shot, full of junk, you've likely burned up the tranny. How does the tranny fluid look, smell? Burned tranny fluid is immmediately recognizeable by the smell and/or black color.

[Trentman]

The tranny cooler line is separate from the radiator inside of it it has its own line so I do not think any gunk would have got into it unless it rusted through but I don't see that happening. The radiatoe isn't cracked or anything just really dirty on he inside I cleaned it out and let it soak in degreaser for a day then flushed it with garden house in the yard. The tranny fluid did look dirty though Im gonna replace the filter and fluid after the head gasket ordeal.

 

I pulled the truck over immediately after it overheated and shut it off. I really really do not want to have to swap the engine. It is leaking very badly however It did not look like the freeze plug was out but yen again I couldent get a real good look at it. I explained the situation to a mechanic and showed him the video that I took of it and he said it's the head gasket. I heard GM used plastic gaskets and they crack and stuff pretty commonly. I haven't had time to really dig into things yet I work 6-7 days a week 60+ hrs, go to college and in the reserves im always on a time hack but I wanna make time for this. The valve cover gaskets were made of rubber does that mean they were replaced previously if they are typically made of plastic or did GM always have those made of rubber and the head and intake gaskets made of plastic? I bought this truck off a guy for 1500 bucks and it's been nothing but problems so far. But I don't mind working on it I kinda like it I learn a lot from these forums and I like figuring stuff out. I just hope it's only the head gasket and not a warped or cracked head.

 

On the milky oil topic I took some oil outta the oil pan and checked the dip stick. It did not look milky or mixed with coolant. However, the tube that comes out of the valve cover and into the air box. Like a purer tube or something. Puked some reddish milky looking oil into the air box. All the coolant leaking out of the head right above where the spark plugs go in looked like it was only coolant.

 

While I'm tearing this engine apart what else would you guys recommend I replace while it's all out. I'm gonna replace all the gaskets, but should I replace the thermostat and water pump just for the hell of it?? Anything else?

 

Thanks for the feedback on everything I really apreciate it all

[Friz2]

If the radiator is full of crud, there is a good chance that the transmission cooler was not cooling anything. That's what I meant, not that fluid could be exchanged.

A cheap flush for the trransmission is to get a five gallon bucket of fluid and connect a hose from the bucket to the input line on the transmission from the cooler. Run a hose from the outlet to an empty bucket. Jack up the back wheels(USE JACKSTANDS). Run the truck, cycle through the gears, and allow all the crappy fluid to fill the empty bucket. I've saved a few seemingly trashed automatics with this method.

 

In 40 years of working with engines and rebuilding them, I have seen ONE head gasket failure without a loss of compression and mixture of oil and water. If you're leaking above the spark plug, it is not a head gasket failure. The head gasket is between the head and block, be low the spark plug. That seems to me to be a possible water fitting for heater or water temp gauge. Maybe a plug worked loose or rusted out.