So I have a 2003 2 DR ZR2 I bought and it's getting close to upgrade time.

I started looking at this thing and what it has for tires and then considering kits etc and what I can upgrade to.

Currently it has 31" rubber on it, with minor rubbing and little to no offset. From what I've read is a "s10 blazer" won't take 31” rubber without a 2-3" lift. I don't feel it has been lifted but I haven't crawled under to see if there was a BL or SL done.

I did have time to measure ground -frame bottom clearance before I left. It was 9.5 inches between the axles.

Anyway, I'm looking for suggestions on everything suspension related, and of course if you think this might have a kit on it already.

My thoughts so far are to try a 2.5" suspension lift, upgrade rim sizes, move to 33" rubber, upgrade brakes to take advantage of larger sized rims, and fix the leveling problem that every blazer has while I'm at it.

 

I`m gonna say that would work. gearing should 3.73 correct? would not go bigger on the tires though, may be to much for the axles

 

ZR2's have a factory lift, and 31x10.5R15 is the stock tire size. So there likely isn't any lift installed on it.


How do you plan on using the Blazer? That will play a part in what tire size you can "fit"


For 33's:
Street only, a 2.5 suspension would be ok with a bit of trimming.
Off-road, full suspension flex on a regular basis a 2" BL would be better. But lots of trimming would still be required

 

Firstly, thanks for the quick support. I always appreciate that.

I hadn't put any thought into axles loads.

The Blazer is a dual purpose vehicle for me. I need to be able to get into some remote stuff, which I will describe at length, but I also need to handle the highway stuff to get there.

Typcially I would drive up to 400 KM (oh yes, those darn Canadians) and then do several days of off-roading, before returning.

The Off-roading is winter stuff. Steep inbankments where approach angles are high, deep snow drifts, dropping off ice shelfs into creeks of a 2-3' depth, fording and climbing out over another steep ice shelf. Also nagivating through river run enviroment that was heavily flooded a few years ago, so a lot of washouts, cut banks, exposed rocky terrian, ice sheets, fords, ice dams that collapse on you as you drive across.

I'm not super experienced at driving this stuff myself but I am no strangers to off-roading and I am fairly certain that last year I took the ZR2 to it's stock limits, and it was a good year out there.

So, in terms of actual clearences required. I had enough to get me over most rocks, and I didn't fall into too many ruts but when I did it wasn't dragging. There is good potentional to spike something if not careful and the skid plates are there on the ZR2.

The last time I was in there a nice jeep wrangler was ahead of me and so he cut trail on the ice dams. They always break as you cross them, which is good but he had water over the front of his hood. No snorkle but it was close as all the water the ice had been holding up drained away. So there are highwater surges if you are breaking trail for the day.

I have three concerns:
-Not being able to climb out of a creek and freezing in.
-Intaking water into the engine while creek crossing or when an ice dam breaks and there is a lot of backed up water
-General ground clearence


How does a factory lift work in this case? I am assuming it's completely different suspension geometry that makes it all happen? I don't know if I need to go to bigger tires. There maybe better ways to get the lift.

To address my concerns I'll also be throwing on a steel bumper, as I smashed the lower plastic valence last winter anyway. I'd feel good about a snorkle and then that just leaves what kind of lift I am going to get. (o:

So that's the big picture right now.

 

ZR2's have different frame mounts to get the lift and width. Upper control arms are the same for a ZR2 or regular blazer.


The 2" suspension lifts do put more stress on the CV's and ball joints, I've been happy with my setup. A good set of 33's and some trimming made a huge difference in the offroading capabilities. Get a real locker for the back and you'll be laughing.

 

So I had a look at your build thread... lol literally every project left me with more questions then answers. =p

Clearly I need to learn a LOT.

First question... I thought dropping into low 4x4 did lock the back. If you say get a *real* locker, as you installed with your build thread, what exactly happens with the *stock* 4x4 low system?

Next question - The rough country sus. lift I looked at drops everything down, including front diff. So shouldn't the angles be pretty close to stock and extra wear n tear be minimal?

Next Question - A body lift basically just gives you more fender room and little else of value? Or am I missing something there. I have very limited vertical clearences to work with. About 7 inches before the Blazer no longer fits into it's underground parking. haha The most spoiled 4x4 ever. (o:'


Next Question - What purpose does a control arm splitter serve? More independent travel of suspension?

 

1. 4lo is just choosing what gearing in the transfer case to use, it's easier on the engine and transmission under certain conditions. ZR2's come with what's called the G80 locker by Eaton. It's an automatic locker that is tricky to get to lock up when you want it to and has blown up on a lot of people.


2. The rough country does drop the diff down a bit, not the full 2.5". So CV's are at more of an angle than stock. The upper control arms do fix the upper ball joint angle, but the lower ball joint is still subjected to extra wear. It won't gain you any clearance during the full range of suspension travel, just raises the static height of the vehicle.


3. Yes, body lift gives extra fender room, which allows for the larger tires. It doesn't sound like a lot but going from a 31" tire to a 33" tire made a HUGE difference.


4. Not sure what you mean by control arm splitter? Are you talking about the sway bar disconnects? If so, then yes it allows for better suspension travel in the front. The sway bar ties both sides together, by disconnecting them you allow each side to move a lot easier, giving better flex.

 

I looked around a bit on the forums about the G80. All I really found was people putting them into none zr2 blazers. Not a lot about people upgrading their blazers.

How does an automatic locker work? If replaced, a manual locker would have to put in while stoped in nuetral via an electric shift?

I might have clearences to do a suspension lift and body lift with tires. If you had to choose between one or the other would to do a BL or get bigger rubber, or some other combination of 2 of the 3 options?

And yes, I meant sway bar disconnects, my mind just couldn't pull up the right words at the time. =p

What kind of offset are you using for your 33" 's? I need to go have another look at your ride. (o:

 

There are lots of good automatic lockers available, just the G80 isn't one of them. The G80 works by a series of weights and springs that engage the locker once there is a certain wheel speed differential between the rear tires. You need to have wheel spin for it to engage.


There are types like the Grizzly locker that are default to the locked position but can allow on tire to turn a bit slower for when you need to turn, but go back to locked once you apply power again.


The eaton e-locker can be engaged while moving very slowly, they have some limit in their instructions. As can the Auburn ECTED. You don't have to be in neutral, but being stopped is good practice. There is also the ARB air locker but requires an air source to lock and is very expensive. The Ox locker has the option of being air, electric or cable operated but is also very expensive.


lol I already did choose BL and bigger tires, every time. There are occasions where a bit more frame clearance would be nice but I don't feel it's hindered me that much.


Camaro Z28 wheels have 4.5" Backspacing.

 

How hard are these Camero wheels to find that everyone seems to be using?

I looked up the ARB air locker. I was interested in installing a compressor anyway at some point so that might not be a bad idea.

Is anyone running a compressor and resivoire system? The compressor just keeps the tank topped up and electrical valves feed things like the locker or air horns when a switch is flicked.