Assuming this is a 5 speed car, the most common reason for this is worn out CV joints. Could also be a bad torque strut.
If it was reddish in color that is just what you did.
You could try changing the transmission filter and the fluid.
I could be wrong here but are you "kangeroo jumping" as in failing to use the clutch properly when changing gears thus the car lurches, this could be a result of a worn out clutch OR gearbox.
There are a couple of reasons why you car is jerking when you are going below 60. It could be the result of a problem with your transmission, or your fuel pump could be going.
Could be in need of a tune up.
This could be due to illness, or poor water quality
Your car battery could be running low so what you could do is get jumpleeds and get an other and jumpwire it
could be a faulty fuel pump.
Could be the gears slipping. Might need new gearbox.
could be the motor mounts as to it jerking if its not the tranny..
If the 1999 Suburban noise is a sort of loud banging noise, the problem could be that the engine have jumped time. Jumping time would cause the noise and jerking in the engine.
If your car behaves as if it's jerking, the problem could be a slippy transmission.