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Old 10-16-2019, 05:09 PM   #51
jaros44sr
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Re: 1972 Blazer Steering

size of the wheel was stamped on mine, save you from dismounting....maybe a belt gone bad on the tire or balance of tire. I had to throw a bag of beads in mine, when you get to 33' tires weights don't seem to work
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Old 10-16-2019, 05:12 PM   #52
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Re: 1972 Blazer Steering

Not sure on the stock ratio but I would think this wouldn’t cause the issue you are having. I think your issue is the tires sticking out differently. Mine are no where near like that. I would say a 1-2mm difference and that could just be human error.
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Old 10-16-2019, 07:54 PM   #53
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Re: 1972 Blazer Steering

not sure but if you have a quick ratio steering, you may be over compensating the input, causing a drift from side to side. As I said, just grasping at straws, No way of telling what's going on from my computer
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Old 10-17-2019, 10:26 AM   #54
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Re: 1972 Blazer Steering

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Originally Posted by jaros44sr View Post
not sure but if you have a quick ratio steering, you may be over compensating the input, causing a drift from side to side. As I said, just grasping at straws, No way of telling what's going on from my computer
Yup!! The last thing you want is a quick box with 104" wheelbase. These trucks are inherently unstable stock.
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Old 10-17-2019, 05:38 PM   #55
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Re: 1972 Blazer Steering

I have unknown angled shim blocks on the rear axle and none on the front. Do these have to match or can I just slap some 6.5 degree shims on the front?

I'm assuming the 15:1 gear ration on the steering box is not "quick ratio", but I have no idea.
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Old 10-17-2019, 06:55 PM   #56
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Re: 1972 Blazer Steering

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I have unknown angled shim blocks on the rear axle and none on the front. Do these have to match or can I just slap some 6.5 degree shims on the front?
The rear is a different animal. No need to match the front. For the front you'll need to first know what your caster is now, then get shims to adjust to 6*.
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Old 10-17-2019, 07:28 PM   #57
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Re: 1972 Blazer Steering

Ahhh, That makes sense....how embarassing
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Old 10-18-2019, 10:40 AM   #58
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Re: 1972 Blazer Steering

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I have unknown angled shim blocks on the rear axle and none on the front. Do these have to match or can I just slap some 6.5 degree shims on the front?
The rear angle shim block is there to make sure your pinion angle is exactly the same as the angle of your transmission. This is so the angle of your front U-joint is the same as the rear U-joint.

You already have 3 degrees of caster built into your front end from the factory. What you want is an angled shim of 3 1/2 degrees. This will give you a total of 6 1/2 degrees.
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Old 10-18-2019, 08:26 PM   #59
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Re: 1972 Blazer Steering

Thanks to the NCDMV I will be trailering the Jimmy to NC tomorrow to be inspected. The good news is I will be forced to enjoy some lake time for a few days and the Jimmy will be going to the only mechanic I trust whom will get the caster and toe-in corrected. Also having them break the front wheels down to see if they can determine why the driver wheel is sticking out.... and rotating the tires.
I'll report back with the results
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Old 10-21-2019, 10:40 AM   #60
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Re: 1972 Blazer Steering

I need 3.5 degrees of positive caster, correct?
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Old 10-21-2019, 10:45 AM   #61
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Re: 1972 Blazer Steering

Pretty sure you're looking for around six degrees.
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Old 10-21-2019, 11:11 AM   #62
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Re: 1972 Blazer Steering

I should have typed "adding 3.5 degree shims" which should give me 6.5 degrees. The shop asked if I was wanting "positive caster" and I said yes.
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Old 10-21-2019, 12:02 PM   #63
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Re: 1972 Blazer Steering

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I should have typed "adding 3.5 degree shims" which should give me 6.5 degrees. The shop asked if I was wanting "positive caster" and I said yes.
Correct. You don't want negative caster, that's for sure.
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Old 10-21-2019, 02:06 PM   #64
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Re: 1972 Blazer Steering

Yes, 6.5 degrees positive total .
I'm surprised the shop would even ask that ! All cars run positive caster. Maybe the shop does alignments on shopping carts too which would explain the confusion. ;-)
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Old 10-22-2019, 11:41 AM   #65
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Re: 1972 Blazer Steering

Soooooo.... after explaining to the shop what I needed in great detail while they smiled and nodded they call me at the end of the only day I could leave it with them to tell me that they don't know where to get the shims to adjust the caster.
I guess I'll be installing the shims myself.
They did rotate the tires and the front driver wheel still sticks out 1/2" further than the passenger side and there aren't any spacers or adapters either. They are dumbfounded as to why because the axle and everything looks original and unaltered.

I added the alignment print out and I noticed what appears to me to be incorrect toe as seen on the tires
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Old 10-22-2019, 12:36 PM   #66
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Re: 1972 Blazer Steering

Is truck a clean title? (ie not salvage?)
How are your door/fender/hood gaps?
Any evidence of an accident or it was jumped?

Something is not adding up here...

1 - Either it's not the stock axle and whoever put that one in there did not do a good job - if you can find the BOM we can narrow that down. Check this site

https://www.differentials.com/techni...dentification/

2 - The frame is bent somehow allowing the axle to shift over like that

3 - Its the right axle....and it left the factory like that????
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Old 10-22-2019, 02:46 PM   #67
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Re: 1972 Blazer Steering

Clean title, all the gaps are good except the hood which curiously is off in the same direction as the driver wheel. That seems likely that there was an impact that has caused both to be off, but the passenger fender is original and does not have any body filler. The frame has been on two frame machines and measured by hand several times. There is no evidence at all showing any type of damage or altercation to the frame or any of the riveted frame attachments.
The front springs went into place without having to be forced over either. The U bolts are in place and vertical (kinda hard to screw up the passenger side, I would think).
I could not find any numbers at all on the axle tube. The diff has the following numbers:
44 5F and c-31256
Is it possible that the long tube was replaced and just not the correct length? There are no signs of altercation and entire axle assembly appears original.
I know I'm not helping, sorry

Unless it was built on a Monday or Friday back in '72 I doubt it came from the factory that way.

I just spoke to ORD about other parts and we discussed the steering issue. He recommended installing a crossover steering kit. Thoughts?
http://offroaddesign.com/catalog/Dana44crossover.htm
I'm still doing the castor shims of course, but I want it to steer better than better.
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Old 10-22-2019, 07:48 PM   #68
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Re: 1972 Blazer Steering

You need to have a shop that knows what they are doing do the alignment. Your truck is NOT stock, but yet they are using factory specs to align it which is not correct. Stock caster specs will not work with lift kits, and most importantly, larger wheels/tires.

As far as your wheel sticking out further on one side, it may have always been like that. I worked for GM for 30 years as a Tool Maker taking care of their jigs and fixtures, and today's cars are built with around a +/- tolerance of 1mm (about .040"). Cars back in the 60's had a body tolerance of almost 1/4", and trucks were worse because they were after-all, trucks. I wouldn't be too concerned about one wheel sticking out a bit further because you're the only one that will know.
Just do the alignment yourself. Get some tapered 3 1/2 degree shims, stick them in, then set your toe to 3/16". There's nothing else that you can do.
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Old 10-22-2019, 08:18 PM   #69
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Re: 1972 Blazer Steering

I've given up on finding a competent mechanic. I ordered the shims and will do the alignment adjustments myself. Thank you for the stress reliever on the wheel sticking out. Crazy but not surprised that I'm the one to get the "special" oddball wheel. I can always install wheel adapters to make them all stick out the same. That way my wife will stop telling me that it's going down the road crooked.... or I'll tell her that I just need a shiny, new axle assembly.
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Old 10-23-2019, 09:23 AM   #70
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Re: 1972 Blazer Steering

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I can always install wheel adapters to make them all stick out the same. That way my wife will stop telling me that it's going down the road crooked.... or I'll tell her that I just need a shiny, new axle assembly.
Don't put an adapter only on one side especially on the front. Moving the wheels further out increases scrub radius so one side would always want to pull in that direction.
If the one side sticking further out really bothers you, then I feel the only solution is to shift the whole body over a bit using the body mounts. (This is considering the frame is not bent)
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Old 10-23-2019, 01:03 PM   #71
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Re: 1972 Blazer Steering

Did you ever check the rims to see if they have the same back spacing? When I measured mine they were even close to being off as much as your picture shows.
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Old 10-23-2019, 08:03 PM   #72
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Re: 1972 Blazer Steering

Well... after hauling the Jimmy 4hours north back to WV and backed her in the garage I noticed the passenger front wheel was not plumb vertically. The wheels were straight forward, so I secured a 3' level and sure as spit was it tilted in at least 1/2"! My $#$%@ driver side wheel is correct, it's the passenger side camber is negative that much.
I knew the camber reading from the second shop that just checked it (as shown in the print out) was screwed up but I didn't have time to investigate.
The shop that "aligned" it two weeks ago is going to love me tomorrow.
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Old 10-23-2019, 09:31 PM   #73
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Re: 1972 Blazer Steering

FWIW, the camber can't be adjusted on these 4X4 trucks. The camber is preset when the knuckles were welded to the axle tubes. Sounds like you have a bent front axle. One side being out that much will definitely make your truck wander all over the place.
Keep us posted !
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Old 10-23-2019, 09:52 PM   #74
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Re: 1972 Blazer Steering

I guess I will start axle assembly shopping. Any suggestions on where to look or any reason to not stay with the Dana 44. I will not be doing anything crazy in this truck. I just wanted a fun Sunday driver for the wife and dog....and me of course.
I greatly appreciate everyones time and effort in helping me with all my dumb questions.
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Old 10-23-2019, 10:14 PM   #75
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Re: 1972 Blazer Steering

I had my Dana 44 rebuilt but only because it was the easiest to do and I never plan to wheel. Beefier difs are nice though so don’t rule it out. I wouldn’t say your axle is shot it could be a bad ball joint or something especially if the shop sucks. I would do some measuring on the knuckle first to see if it’s lined up right and check the ball joints. If they are old replace them. It’s not hard to do just get the right tools. No need to have a shop do it. Camber can be adjusted, but it requires a special ball joint which I have never heard good things about and if you put in a good ball joint it won’t need adjustment.
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