What size lift do I need for my 72??

[justincasey57]

I deleted the wrong post. I still need opinions on weather I need a 6" of a 8" susp. lift? i have a 3" body and flipped shackles in the rear and 2" hangers in the front and 4" susp. lift now and i am clearing 35's perfect.I am wondering what yall are running i am trying to get 39.5's under it I'm not doing ANY offroading at all.Just street only.The 39.5 iroks are going on 20x10 wheels.If you have any pic's it would help a lot!!thanks

[earl87gta]

I had 38 with 6 spring and 3 body. boostat4500 runs 38 with only 6 springs but he does no off roading.

[justincasey57]

still need more opinions please!!!!!!!

[earl87gta]

here is a burb with 6 lift no body on 38s. I would think you would be ok if you kept your body lift and ran 6 suspention. http://67-72chevytrucks.com/vboard/s...d.php?t=253781

I couldnt find any pics of mine with the 38 only with 36s but Im sure if I wasnt wheeling it 3 body and 6 spring would have been ok with the 39s.

[justincasey57]

Yea I have been talking to him about his burb any other info???Thanks

[justincasey57]

Need More Opinions Please!!!!!!!!!!

[justincasey57]

anybody????

[justincasey57]

any pic's ?

[justincasey57]

[jaros44sr]

It's only two days since you first posted, give it some time for people to reply. We're here to help, not fustrate ya. In the meantime you can surf the site, plenty of pics in here

[1969k10stepside]

I think you will be fine with 6" suspension lift and 3" body lift.I assume you plan to adress steering and braking upgrades with the bigger tires? Those should be kept in mind.Stock steering and brakes don't go good with 39s even if you keep it on the street.

[justincasey57]

yeah the brakes have been extended but no upgrades as far a heavy duty brakes or calipers.the steering needs to be adjust the way it is now but i'm waiting until i get it complete and they adjust the draglink.thanks for your input.

[special-K]

True 9" would be adequate.If you recall,I know from experience that 7" w/37s worked excellant on my`71 Blazer.I had 8" wheels.Alot depends on wheel width.With 38s some guys run 12" and if that`s the case,I`m not sure you`ll have full suspension cycle w/o contacting the front fenders.

[vtblazer]

What axles are you running with those tires?
Be safe first and foremost, do the brake and steering upgrades before you run the roads with it.

Special-K and I both posted alot of valid info in the last thread, what more are you looking for?

Your front fender opening is only 38"s, both the front fang and the rear drop will hit tires that large when turning unless the lift is sufficient.
If in fact you do have 9"s of total lift, it'll be close even still.

Is trimming at all in your thought process?

A question for you:
Have you ever run a tire that large on the street?
Are they radials?
If their not radials, fair warning.
The street manners aren't so great.

[justincasey57]

Yea I've ran tires that big and no there not radials. a buddy of mine has the same set but with 16" wheels and his truck drives like a dream.I've always ran radials or A/T's but i've heard if you drive them a lot and there not sitting for days at a time they will be ok esp. when they get hot. ?The axles are just stock dana 44 and a GM 12 bolt.350 motor with turbo350 and 205.I thought about 3/4 or 1 ton axles but I'm only using this truck on the road.I WILL NOT CUT THE FENDERS.I hate the thought of a good looking truck being hacked at.

[justincasey57]

VTBlazer I will actually have almost 11" of lift. I decided to get the 1" blocks from ORD(zero-rate) for the front.Along with the 6" susp and 3" body and the 2" in. shackles in the front.(i figured the shackles are only 1 inch since it only lifts one side.)

[vtblazer]

Originally Posted by justincasey57

VTBlazer I will actually have almost 11" of lift. I decided to get the 1" blocks from ORD(zero-rate) for the front.Along with the 6" susp and 3" body and the 2" in. shackles in the front.(i figured the shackles are only 1 inch since it only lifts one side.)

Originally Posted by justincasey57

Yea I've ran tires that big and no there not radials. a buddy of mine has the same set but with 16" wheels and his truck drives like a dream.I've always ran radials or A/T's but i've heard if you drive them a lot and there not sitting for days at a time they will be ok esp. when they get hot. ?The axles are just stock dana 44 and a GM 12 bolt.350 motor with turbo350 and 205.I thought about 3/4 or 1 ton axles but I'm only using this truck on the road.I WILL NOT CUT THE FENDERS.I hate the thought of a good looking truck being hacked at.

Would have to think 11"s would do it.

What about the gears?
Any idea on your current ratio?

The thing about the 3/4 ton running gear isn't just about the axles, it's also about the bigger brakes and better stopping power.
Changing out the booster/master to a 3/4 ton set up is a good idea to do too.

You say "just on the road" but that's exactly where your going to want/need the brakes and the steering to go with it.
It's a bad day all around when a car pulls out in front of you and you can't stop.

So with 11"s of lift, your running cross over steering already?
Yet another smart mod for running big lift and big tires.

Be smart and be safe for your own sake and everybody else on the road.
Build the truck right the first time.

[justincasey57]

no, crossover steering is on the way.the brake booster that was on the truck went bad i went to replace it and found out it came off a C30 not a 1/2 booster.This truck orig. had 13" of lift and had 38.5's on it and the guy i bought it from took all that off and I got it stock with a 3" body.The gears I think are 3.73 not sure if the orig. guy who built this truck to begin with put heavier duty brakes on these axles or not??

[justincasey57]

With this much lift and these size tires should i look into crossover steering or adjust the drag link???

[bowtier]

Originally Posted by justincasey57

With this much lift and these size tires should i look into crossover steering or adjust the drag link???

Originally Posted by vtblazer

with 11"s of lift, your running cross over steering already?
Yet another smart mod for running big lift and big tires.

Be smart and be safe for your own sake and everybody else on the road.
Build the truck right the first time.

I agree with VT. (emphasis added by me)

And FWIW, I don't feel a 1/2 ton with 39.5" tires and no other mods is even safe to drive on a public road. Just not a good idea. Don't get me wrong, I'd rip the 1/2 ton around the field/trails all day....or til it broke. But the minute you pull onto a public road you along with everyone else on the road is in greater danger because the truck won't be able to make quick evasive manuvers to avoid an accident.

Not trying to ruffle your feathers, just trying to explain one point of view.

Safety first.

[-Greg72]

Originally Posted by justincasey57

With this much lift and these size tires should i look into crossover steering or adjust the drag link???

You'll need crossover steering.....it's not really a debatable point.

3.73s are going to be lousy with such a large tire and small motor. It's a phenomenal amount of rotating mass to get rolling. It's going to really put a lot of twist against those 1/2 ton axleshafts too.

Which leads me to the next point....a 12-bolt rear axle is a semi-float design and when you break an axleshaft (which you probably will with that much tire) the remainder of the axle shaft and your entire wheel will fall out of the axlehousing and off the truck. Not sexy...

A smart move would be to go with a 14BFF axle out back....they are cheap and strong and are a full-floater axle, so no worries about losing a wheel. You can usually find them in 4.10 and 4.56 gears without much effort. You'll want that deeper gearing to compensate for such a heavy tire anyway.

Up front, you can do an 8-lug conversion to your existing D44, but unless you are building a truck for the mall, it's kind of a waste to spend the money on crossover steering on a D44 axle. If you leave the front axle unlocked (no locker or posi) you might do OK with it.... but it you want to really wheel it, a D60 front axle is the better choice.

It sounds like you already have steering issues that need immediate attention. If the axle was moved forward from the stock position due to the lift, then your draglink is too LONG, and you'll never get it to turn correctly. You need to figure out how many inches forward you are from stock, and cut that amount of length out of the draglink. You will end up with equal amounts of turning (left and right) but with such a short draglink, you might not like how limited your turning radius is. A shorter draglink is also going to amplify "bump steer" on the road....so it's likely to be miserable to drive, especially on the highway. It's going to really pull you all over the road whenever you hit a bump, or hit the brakes hard.

[special-K]

Originally Posted by -Greg72

You'll need crossover steering.....it's not really a debatable point.

"Non-debatable?"Does this mean I haven`t been able to steer my trucks all these years?Please explain.



Up front, you can do an 8-lug conversion to your existing D44, but unless you are building a truck for the mall, it's kind of a waste to spend the money on crossover steering on a D44 axle.

It`s for the mall.

I haven`t been to the mall in my truck and unless I try some real extreme (IMO) 4 wheeling I have no problems w/o crossover steering which never existed as an option until recently.
I agree,going with this amount of lift and large tire size there are alot of other points that need addressed.We`re here to help and 4wd magazines and books have all you need to know and they all will agree running tires of this size are not a bolt-on thing.It gets expensive over 35".
I do plan crossover/high steer on my next 6" lifted truck I have planned.But,it only makes a difference in real twisty circumstances that most trucks don`t get into.There`s an endless list of offroad enhancing mods,but you can get by w/o most.It`s all a matter of limitations.

[-Greg72]

SpK,

With crazy tall lift, there's almost no way to get the draglink into the correct horizontal position again (except for dangerous steering arm spacers, etc). Having the draglink at a severe angle is going to adversely affect steering...and not just offroad.

If the axle is moved forward (as it sounds like it is in this case) that draglink is going to need to be shortened to get equal amounts of "left" and "right" steering. An even shorter draglink will be less tolerant of bumps or hard braking and will either want to pull or push the steering wheel as it drives. I learned this one on my own truck when I moved the front axle 1" forward. The truck was a real handful on the highway, and that was only with 4" of lift and 36's. The swap to crossover steering was a night-and-day improvement in driveability, and my turning radius (at the mall ) was dramatically better also....

[justincasey57]

I hear ya, is there any upgrades I can do beside changing axles?(brake upgrades)I am wondering if he did some brake upgrading before I bought the truck because like i said in the above post i went to replace a bad brake booster and got the wrong one and took the old one up to the parts house and came to find out it was off a C30.???Makes me wonder??(the guy had 38.5's on it at one time)

[justincasey57]

thanks for the info.I will check into axles and gears but the only thing is I just bought brand new 6 lug 20" wheels for this thing.