Re: 1972 Blazer Steering
 

Straight axle chevys wandering is always due to frame flex or cracks.
The steering box mounting area is frequently cracked and usually not readily visible.
The front crossmember rivets are almost always loose.

Inspection for cracks: 2 person job, one person moves wheel left snd right while another uses strong lighting to inspect the frame inner and outer around the steering box looking for cracks to open up.

Inspection of rivets: 2 person job, one person shakes wheel left and right the other person holds the rivet and then the crossmember and frame, the rivet should not move nor the frame and crossmember. Repair with bolts that fit the holes very tight, rivet replacement procedure is in the chassis manual i think if you want to look it up.

With a stiff frame the wheels transmit their force through the tie rod to the steering box which restrains the wheel from moving which causes the darting around.
A cracked frame and or loose rivets doesn't restrain the wheel and the truck darts around.
These things are never found via alignment.
Front end mechanics dont look for this stuff.

Off road design has a steering box frame reinforcement and a bracket that ties the drivers frame rail to the crossmember which further stiffens up the front frame.

Loose or missing engine crossmember bolts are also frequently found too. The engine crossmember also ties the front frame rails together.

Re: 1972 Blazer Steering
 

/\ /\ /\ /\
That's not entirely accurate ...

https://youtu.be/tKsyifhXZwY

Re: 1972 Blazer Steering
 

Maybe check the frame to see if its square... cross measure from common points... this is a 71 but most points should be the same...

Re: 1972 Blazer Steering
 

The ball joints and tie rod ends were just replaced prior to my purchase, but I will double check them.
The cracked frame/ loose rivet scenario was the first thing I checked for when I first bought it because of the steering issue. I thought it was just a worn out gear box. I thouroughly examined the frame, etc. before, during and after installing the new one.
Despite it still being solid, I did order the ORD steering box frame bracket that you mentioned. Hopefully it will fit! The big block may be too far forward?
Nice builds and helpful links Randy. The doors are getting gutted this winter.
Thanks Rich, those are the specs I used to measure everything and all was good.

Re: 1972 Blazer Steering
 

interesting didn't know that, thanks for the you tube

Re: 1972 Blazer Steering
 

I think I'll just show my wife that beautiful axle assembly and she'll make me order one

Re: 1972 Blazer Steering
 

Not sure where I was not accurate. I somehow don't think the OP's truck has an aftermarket camber adjuster. Even if he did, those adjusters only allow for a little bit of adjustment. They are not designed to repair bent axles.

Re: 1972 Blazer Steering
 

Great info from everyone, thank you. I believe my issue may be beyond what the gadget on the YouTube video can correct, but I'm glad to know it's out there for potential future use.
I just double checked the ball joints and everything is tight.
I think I just scored a professional shop and all they do is axle and drive shafts. Two co-workers have had insane custom work done to their jeeps there with great results. They're currently working on two '72 Scouts and a C10, so they're not only Jeep guys.
It's going to take a couple weeks to get it in, but I'm starting to feel confident that all will be well very soon!
I will report back in a few weeks as soon as I info to share.

Re: 1972 Blazer Steering
 

Before you take it to the shop (highly paid parts changer) get a friend and check the frame, maybe 2 fiends, i guarantee you have component movement/looseness that needs to be found.
frame, crossmembers, pitman shaft, im sure all of those are loose. Possibly ball joints and or tie rod ends.

Re: 1972 Blazer Steering
 

Bent axle aside they also make shims that go behind the spindles to adjust camber on Dana 44s. Just google "Dana 44 camber shim".

Re: 1972 Blazer Steering
 

I'm going to throw this question on this thread since we are discussing steering related items. I can't find another thread that discusses it.
My frame is solid but I want to prevent future issues by installing a steering/ gear box brace. I ordered one from ORD but it won't fit because my engine is too far forward. Does anyone know of a good bolt on brace that would fit with a big block?
OR! Does anyone make an aftermarket crossmember that also supports the frame better?

Re: 1972 Blazer Steering
 

I'd take your question back to ORD and see what they say.

Re: 1972 Blazer Steering
 

What is causing the engine to be too far forward? I have a 4l80e in mine and I was able to install their kit. It’s close but not too close.

Re: 1972 Blazer Steering
 

This may not be helpful info but K5's have a factory brace for steering box at the frame ( http://67-72chevytrucks.com/vboard/s...61&postcount=1 )

Re: 1972 Blazer Steering
 

This is why mine won't fit: (From ORD: '72 and older with big block motor in the factory big block position may have interference between the crank pulley and box brace, you need approximately 3" from the crossmember to the pulley for the brace to fit.)
I emailed them, DIY4X and some others inquiring about a custom built beefy, front cross member.
The attached pic is not my truck, but mine does have the factory gear box reinforcement as shown.

Re: 1972 Blazer Steering
 

Mine has the same reinforcement. I didn’t use their part that goes in that spot. I have my LS3 pretty far forward and don’t have interference. I bet it would fit.

Re: 1972 Blazer Steering
 

Going back to the previous discussion about my erratic steering: The axle and drive shaft pro shop I took the Jimmy to told me that the axle was bent in two different directions! That has been corrected and I hope to pick her up next week. They are checking everything else out, aligning it and custom making new driveshafts.
I can't wait to drive it and not chase the front end all over the road. I will report back as soon as I confirm all is fixed.

Re: 1972 Blazer Steering
 

There we go! I kept thinking something is just not adding up with your issues and thought things might be tweaked. Looking forward to your follow up on this one...

Re: 1972 Blazer Steering
 

The shop called me back today with the "good news/ bad news". I'll skip to the bad. My rear axle is also bent. The front was bent in a horseshoe and the rear as well. Both facing the center of the vehicle. We assume that someone transporting it at some time used chains and binders to haul it and bent the axle tubes.
At least it's getting fixed, but it will be another 2+ weeks and I have all kinds of goodies to install: Boyds gas tank, new steering column, steering wheel and instrument cluster (w/tach and vacuum).

Re: 1972 Blazer Steering
 

I drove the Jimmy home last night. An hour drive on winding mountain roads and she is 90% better after getting the axle tubes straightened.

Re: 1972 Blazer Steering
 

Very cool; you think you can get the last 10%?

Re: 1972 Blazer Steering
 

Yeah, caster shims !

Re: 1972 Blazer Steering
 

My percentage rating is skewed as the only base I have to go off of is the horrendous way it previously steered and comparing it to our brand new vehicles.
Previously driving it I encountered several near death experiences. I drove it home violently and was very pleased.
I bought the caster shims but didn't get them to the shop before they already corrected and reinstalled the front axle assembly... so now I get to do it.
The straigtened axle tubes corrected every issue that has haunted me since I got it. The leaf spring shackles are even, the wheels are centered in the wheel well, the front passengers wheel is VERTICAL and as stated, the steering is corrected for the most part.
I'm amazed that they could have been that screwed up and I couldn't tell no matter how many ways I have checked them.
I greatly appreciate everyone's time and effort helping me.
I'm sure I'll be on here begging for help with all the goodies I'm about to install.