Is yours a 4x4?

 

Yes, 4x4.

 

Well I guess I shouldave gotten 1 7/8...

Installed 1 3/4 tsp headers and y today. They offer 2wd and 4wd headers. Good news is they fit, bad news is the y pipe mightave came from the same factory as the speed engineering y lol. Same clearance problems with the driveshaft and trans pan. I'll start a new thread with pics and stuff.

 

Do you have s lift or any suspension mods? Seems odd that two separate companies products wouldn't work. Unless they do come out of the same factory. Lol. Maybe it's just an avalanche thing?

 

Mine is stock suspension, I have room for days around my driveshaft. My driveshaft is significantly skinnier than the factory 4l60e one though (stock out of a duramax truck).

 

My 1 3/4 on my Denali hit in several places. They rubbed the steering shaft, they had the passenger o2 up against the floorboard/firewall, then two other spots I flattened the pipe just to make 100% for sure no vibrating. Everything is great now. Im not bitching, for the price I didnt mind.

 

Kinda curious now about how my headers are going to work out with adding cats to them on my lifted 4wd.... With the cat pipes and stock manifolds i still have on at the moment, my passenger side pipe is quite closer to the floorboard and at idle it thumps it, had fixed it once before, but after changing my trans mount it started doing it again, seriously thinking about some new polyurethane cab mounts in the short term plan for the truck!! And maybe the body lift i havent been able to bring muself to install yet for various reasons!!

 

For those concerned, we do stand behind our products, and a full refund was issued to Formula96. We will look further into the Avalanche chassis fitment.

Thanks
Sean

 

Almost seems worth it to pay more for a better product.

 

Define better, have rear of fitment issues with every brand of header, in one way or another... Is it nstaller error? is every truck exactly identical to the next? Considering how many different factors there are it would be damn near impossible to build something that someone isnt going to have an issue with.... Headers fall into the category of custom exhaust, or they should.... To expect to not ever have to modify something slightly to make it fit, defeats the purpose of buikding anytbing