Suspension Problem or something else???

[low82c10]

i have a 82 c10 shortbed, it has never had this problem till after i towed it on a flat bed trailer. i loaded it on a flat bed and it was center of the trailer, when i arrived to the shop, the truck was all the way to the front of the trailer which it moved two feet foward. i didnt really think any thing of it, yesterday i test drove it after the exhaust shop finished up my exhaust and i makes like a clunking noise when i turn left. what should i check out? it drives fine everything else seems ok but just when i turn left it clunks and it goes away a few seconds after driving straight.