87 suburban need help

what color is the exhaust? If it is white....then you have a blown head gasket and the antifreeze is mixing out the tail pipe. That is a big $$ problem. Also depends how long this has been going on, for it is caustic to the engine.

I have an 85 GMC Suburban and I analyzed that a thermostat was the original culprit that started the spiral down of my engines performance. Try that inexpensive part first. Another key indicator was that I had no heat pumping thru the heater. Do you have heat??

Yes it has heat and the thermostat got changed when he did the intake gaskets

The smoke is white it started blowing out a lot more smoke after I got the intake gaskets and thermostat changed it's only been driven 3 or 4 miles since it started doing this now it's parked in my driveway

There may be problems with the engine block, and coolant may be leaking in to the engine because of a leak in the head gasket

There are a few wild products at Auto Zone that cost $30-60 that fill in where the leak is happeneing. Like "Blue Devil products" plus others

There are some makes or models of cars that have a reputation for blowing head gaskets.  One vehicle I owned had such a bad reputation for head gasket problems it there was a group of owners trying to get the manufacturer to have a recall on them.  If you happen to own one of these vehicles, don’t worry it does not mean that you have a bad car or that you are going to spend lots of money. The head gasket forms a seal between the engine block and the cylinder head.  This seals both the combustion chamber and the coolant passages in your engine.  This means your head gasket has to seal both extremely hot high pressure combustion gases as well as engine coolant which can be anywhere from cold ambient temperatures to the normal operating temperature of your engine.  Do to the wide range of temperatures and relatively large surface area, it is not unusual for head gaskets to develop leaks over time. Since the head gasket seals the coolant passage both from the atmosphere and the combustion chamber you can’t see or get too much of the head gasket on a vehicle.  Because much of the gasket can’t be seen without disassembling the engine, it can be very difficult to diagnose a head gasket leak.  Since a visual inspection usually will not prove a head gasket leak, it is important to know the other symptoms so you can accurately diagnose a head gasket problem. Blown Head Gasket Symptoms: Coolant leaking externally from bellow the exhaust manifold White smoke from the exhaust pipe Overheating engine Bubbles in the radiator or coolant overflow tank White milky oil Significant loss of coolant with no visible leaks The only externally visible sign of a blown head gasket would be coolant externally leaking from the head gasket.  The head gasket will be below or inboard of the exhaust manifold.  Most head gasket leaks will be between the combustion chamber and the coolant passage in your engine.  On the intake stroke of the cylinder closest to the leak, coolant will be drawn in under the vacuum created along with the intake air charge.  Upon combustion, the high pressure will force exhaust gases past the head gasket into the coolant passage.  This process will repeat itself for every revolution the engine makes. As coolant is pulled into the combustion chamber it will cause your engine coolant level to drop.  This can cause a low coolant light and overheating if the cooling system on your vehicle is not continually topped off.  Also, once your engine is turned off the coolant still left in the engine cylinder will seep past your piston rings into your engine oil.  Coolant mixed with oil will make a white milky substance.  You may see this on your engine oil dip stick or on a ring around your oil cap.