need some help with cutting fenders

[89burben]

i have an 89 suburban 2500 4 inch lift and it sitting on 35x12.50 now and im pick up a set of 39x16 will i have to cut my fenders or will i be able to clear them no problem????

[grayblazer]

I have a '90 K5 with a 4" lift and 39.5x15 TSL's, so almost identical to what you are asking. If you want to be able to turn or hit any type of bump without mashing the fenders hard or cutting up the tires the fenders will need significant trimming. Not even sure if the tires would clear just driving straight on a flat road (by the time I had 39.5's the fenders were already trimmed quite a bit). Over the years I've had 33x12.50 BFG Muds, 35x12.50 Goodyear MT/R, 13/38-16 TSL (closer to a 37x12), and now 39.5x15 TSL's with a 4" lift. When I went from the 35's to 13/38's the front fenders were slightly trimmed for off-road use and I could not even turn the wheels back and forth sitting in the garage without them hitting hard. It took a decent amount of trimming to just allow enough clearance to drive it on the road, and quite a bit more to clear when off-road. The 39.5x15's took a lot more trimming to work and they still rub slightly. On the front fenders, I'm back against the firewall and have trimmed and bent the pinch seam back for clearance and on the front it's against the core support.....basically as much trimming as possible without drastically modifying either the core support or firewall.

[89burben]

i think ill just find a set of 37x12.50 i had them on there before the 35's but they were bald and i didnt have money for new 37's but i dont want to cut my fenders that much