Step Notch/Super Notch.....whataever its called...

[kewljay223]

Hey guys. Im trying to get ready to pull off this kind of notch here pretty soon. If you saw in one of my recent threads, im gonna grab some new tires to help with some traction issues im having. And in doing so the tire thickness is going to grow between and inch or two depending on the size i decide on. prolly gonna go the 285/50 route vs the 235/35 i have now which will gain me around a 2.5" lift in the rear. this will significantly rake the truck which i personally DO NOT like. so in order to keep it level i will need to drop it back another 2" which i will do by some drop shackles i just purchased. But i will need to notch my frame more and i dont want to cut into the bed more than i have to since i use it.

I know i need to buy the tube steel and some plate steel for the sides but i cant find any info on what the thicknesses are. im not gonna buy a kit as i can fab it up myself. my question is....what is the sidewall on the 2x tube steel and the flat stock that the kits or guys fabbing these up? i wanna say at least 1/4" but some pics i see on the net look thicker... like 5/16 or maybe even 3/8.

i dont want to spend more than i have to but i want it to be structurally sound as i will be towing a 20' boat. what are you guys using so i can get the right stuff?

here is a pic of what im talking about

[kewljay223]

oh i almost forgot. anybody running this kinda notch.... will i have to cut the bed just above the pumpkin for clearance? does it smack into the floor??? from the measurements i took on mine, it looks like it will hit the bed floor by about an inch at most... im pretty sure i will need to re route my brake line which is still routed over top. but will the pumpkin still hit? thanks

[jeast]

If u dont want to cut into the bed, just pick up a flip kit. The rear flip kits normally all come with a bolt in c notch. Im not sure what ur running for wheels but, u can normally get a wider tire with the same or similar OD. I've gone from a simple c notch to a full fab frame notch. The big frame notches can be tricky to keep ur frame straight. It has to be well planned and supported. Looks like u already have the truck lowered, it should handle a full 4/6 drop with no problems at all. tell me exactly what ur running for tires and wheel width and ill find u a wider one that's a good match.

[Jeebalow]

There's pics with a tape measure here of the AVS underbed notch. Looks like 1/4" all around.
http://www.gmfullsize.com/forum/showthread.php?t=136114

And here it is just bolted in:
http://www.gmfullsize.com/forum/showthread.php?t=92884

I have the same notch, but it's at home 1.5 hours away so i cant get dimensions for you. If you still need them by next weekend PM me friday and I'll measure for you.

[kewljay223]

Jeeb, thats awesome. thanks a lot. and i saw that second link a while back. couldnt find it again though. great pics in there. and yes, it does look to be 1/4" for the tube steel. and the plate looks the same so im betting 1/4" also.

and jeast, my truck is already 4/6 with the axle on top which is the flip kit right? also i have stock shackles. and your right about keeping the frame straight. but this wont be an overnight thing. thanks for the heads up.

right now i have 235/35/20. i need more meat in the back for traction so im planning on getting either 275/45/20 or preferably the 285/50/20. the 285 will increase the tires wall thickness 2-1/4 - 2-1/2 inches which in turn will raise the rear of the truck that same amount and i dont want that. so i bought 2" drop shackles to bring it down. problem is my axle is only 2" from current c-notch. so i need the super notch to get my 2" clearance back.

but i would like the notch to go ALL the way to the top of the frame. the AVS kit looks like its down about 3/4" from the top. I need all i can get. also i just saw a post somewhere that a 3x12" cut in the bed above the pumpkin was all that was needed, but required. so that answers my other question.

so it looks like 1/4" is the way to go. ill start hitting the scarp yards. i plan on welding this all to the frame rather than a bolt in. but do you think i should throw in a few bolts just for good measure or is that just overkill? thanks for the help guys!

[jeast]

Falken makes the fk453 with the size u need, no need to change tire diameter
275/30ZR20 97Y 28605001 9.5 9.0 - 10.0 26.5 10.9
285/30ZR20 99Y 28605013 10.0 9.5 - 10.5 26.7 11.4
The tires u have now have a 26.5 OD, you could use the 285/30zr20 no problem. The other thing ur over looking is if the tire u choose is 2" bigger in OD, it's only going to raise ur truck 1" not 2". Either one of these two tires listed would keep the proper OD but they could be a tight squeeze to get on to a 8" wide wheel.
Hope this solves ur problem.

[kewljay223]

Hmmm... i kinda had my mind set on the yoko parada's... now you throw this into the mix. i did a little search on them and they seem to be pretty good. have you ran them? hows traction?

your right about the the tire height, but i was measuring the aspect ratio. 235/35 = 3.23" and 285/50 = 5.61" wall thickness.

and i am concerened about the width of my rim also for them to fit... i think its larger than an 8 but im not sure. i have to somehow find my recipt for them.... if i have to ill go with 275's

[jeast]

I run falken tires. There a good bang for ur buck. The parada is a good tire but way over priced. The 285 50 is a huge tire. I wouldn't even run that on my GM. The width is fine it's the diameter 31.5". That's a huge jump from ur 26.5. I've ran nitto nt404, Toyo Proxes, now falken tz04. There all good. I sold tires for years as part of my business. Tried selling yokahoma but not many buyers, sold tons of falken's though. U would save ur self a lot of headaches if u stay close to the same diameter. All tire manufacture sits have charts to show the diameter, section width, recommend wheel width ( only recommended for performance and wear not 100% necessary). So don't worry about calculating dimentions.

[kewljay223]

yeah i know its a huge jump. lol thats why i was planning on the notch. i kind of got the feeling you were in the tire buisness.

what do you mean the parada is over priced?? i thought it was a pretty good deal for how great it performs. my tire/wheel shop i use is selling the parada for 170 and the fk453's for 240... decisions decisions!!

[Jeebalow]

No problem man. If you are welding it in, you absolutely do not need the bolts. The holes are actually stress risers. The area immediately around the holes will see about three times higher stress than an undrilled area under the same load. Just make sure the welds are good to maintain structural integrity. If you notice, the AVS notch also hangs below the frame. You can see the circled areas below are where you could raise it. I am planning on installed and welding it so it is as big as possible when I install mine.

*pic from marcos on gmfs

You can use a section of 2"x2" 1/4" wall and plate it in like the AVS notch, but go to the top of the frame.