Bouncy front end

Hi I have a 1989 Ford Mini van. Has a very strange thing happening in front end. It sometimes bounces right and left and pulls hard to the left to the point I have to pull over and stop. It only does this “rarely” thats the weird thing. I have brand new tires yet it did this before the tires. Im not sure if its coincedence or not but it seems to do it more in hot weather. I feel like the shaking is maybe a tie rod? or why would it be only intermittent and not all time? im stumped. It has done it about 2 times in 5 months thats how rare this is. Right now I get in and it drives fine . straight down road. any ideas?

I meant it pulls to the right not the left

You need to get this vehicle to a front end shop asap to find out what is wrong with it. That sort of problem on the highway could cause an accident, the results of which will have to be on your conscience forever for knowingly driving an unsafe vehicle. As far as the problem you are having, it may help to know exactly what model your van is. I will assume Aerostar since that is the closest thing to a minivan Ford made in 1989. Aside from a general front end inspection, which a vehicle this age needs anyway, I would look specifically at the sway bar and shock absorbers. Worn shocks could definitely cause this with the twin I-beam suspension I’m pretty sure this vehicle has.

Have the ball joints, tie rod ends, struts and stabilizer bushings checked.