398HBX's Build Thread - Engine is IN!

[398HBX]

Finally got over the winter blues - did a little work

I finally decided to get off my ass and do something. So this weekend I took the front axle off the K20 burb and brought it into my shop so that I could work on it. So far I have the steering knuckles off and the axles out. The steering arm was not as bad as I thought it would be to get off. A little PB Blaster and a really BFH and that puppy just popped right off. I pressed out the old ball joints and replaced them with new MOOG ball joints. I still have to finish cleaning up all the parts, get them painted, and then try to tackle the carrier housing. As it is right now, I plan on replacing the wheel bearings and seals and all of the tie rod ends. I am not sure if I want to take the ring and pinion out to replace the pinion bearing and seal beacause I am not sure how to set the gears back to where they need to be. Then again, I might as well try? I have been taking lots of pictures (too many to post here). I will work on providing step by step tear-down and rebuild procedures on my build site (www.398hbx.com) for anyone who needs it.

 

[y5mgisi]

New ball joints! Good feeling.

 

[mrwilliamsburg33]

I checked your site out... pretty cool. And just to confirm, any pictures with details explaining anything you do will be helpful to many people. I haven't done much to my blazer yet... waiting for time and money... but am always interested in seeing what others do.

 

[398HBX]

I bought the Rancho 9000 shocks but have not used them yet. How do you like them so far? Any problems with adjusting them?

 

[mrwilliamsburg33]

This blazer is actually the second vehicle I've put them on. I previously owned a 95 GMC Sierra 1/2 ton shortbed. They were great on there. So I figured I would try them on my blazer, and they've been good on it too. Made a decent difference from the old stock shocks to those. I haven't adjusted them any, just because I haven't had the need too or just haven't made time to play around with them. I had them set to around 5, I think there are 9 nine different levels. I did not buy the wireless remote either. But I think they are good, I have no complaints anyways.

I bought the Rancho 9000 shocks but have not used them yet. How do you like them so far? Any problems with adjusting them?

 

[398HBX]

Front axle limited slip/locker dilema

OK, I am rebuilding the front axle for my K5. It is a GM 10 bolt, 28 spline, 4.10 gears off a 1986 K20 Suburban. The rear axle is a 14BSF, 4.10 gears, with a Gov-Loc. I know that I should probably axe the rear diff and get a new one but I can't do it right now. I was thinking of putting a either a limited slip differential in the front but I am not sure if it is even worth doing. This truck will be used for limited highway, mostly offroad in moderate conditions (no rock crawling or "Hey, Can I get this stcuk?). I just want a truck that when I take it out in the woods to hunt, scout, or whatever, I can be reasonable assured that I can get there.

Options:
1. Do nothing, leave as is.
2. Detroit True Trac Limited Slip Differential in the front 10-bolt
3. Powertrax Lock-Right (model 1920) in the front 10-bolt
4. ARB RD83. Nice option but expensive and kind of a waste with the gov-bomb in the rear.
5. Buy a GOOD winch.


Any thoughts, comments, opinions would be appreciated. (I know, opinions are like butts, everyone has one and they all stink). I just don;t want to waste money for something that I don't need.

OK, I made a decision based on end use, $, popular opinion. I decided to go with the Detroit Tru Trac

 

[398HBX]

GM 10-Bolt, 8.5", 28-Spline, Front Axle Teardown

I finished tearing down the front axle for by Blazer. I have most of the parts clean, but I still need to put in the new bearings, seals, etc. I am a little nervous about installing the Tru-Trac since I have never messed with the differentials before. Then again, what is the fun in doing something that you always do? I took a lot of pictures during the teardown, too many to put here. I have updated my build site with complete tear down instructions on how to remove the front locking hubs, hub,rotor assembly, steering arm, steering knuckle, etc. Many of you already know how to do this, the site is mainly for my own sanity so that when I go back to putting it together, I have pictures on how it is supposed to go.

If you go to the site, do me a favor and leave me a comment.

http://www.398hbx.com/home/gm-10-bolt-8-5-front-axle-rebuild

 

[magik235]

Outstanding thread. I will follow it.

 

[398HBX]

Excited, Sacred, and Just a little intimidated - TrueTrac Arrived Today!

I got home from work today and found these on my front porch. I am excited, scared, and just a little intimidated all at the same time. I have never messed with a differential before and there is very little detailed information out there on how to do this (at least not that I could find). I figure if I take my time, measure EVERYTHING, take good notes, and lots of pics I should be OK. At least then you guys can tell me when I'm headed in the wrong direction. I'll probably start the install this wekeend, I want to be sure that I have plenty of time and not rush.






Detroit TrueTrac LSD for GM 10-Bolt, 8.5" Front Differential

 

[magik235]

Nice

 

[y5mgisi]

Very!

 

[398HBX]

Figured out how to properly check backlash (I think)

1. Remove
I have a manual, used several websites, and checked the CK5 forums. Lots of usefull info out there but I was still not clear. After a 3 min Youtube Video, I slapped myself in the head and said "Duh!". Here is what I did.​

Step 1 - Inspection​

Ring Gear Tooth Terms​

​

1. Remove the differential cover and inspect the gears for signs of excessive wear or damaged teeth. Clean the inside of the differential with carb cleaner or other solvent to remove any excess oil. Wipe dry. If no damage is observed, proceed to next step.​

Step 2 - Check Ring Gear Backlash

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It is always a good to idea to know where you started before you rip into things. Take lots of pictures and notes. This step will describe how to check the backlash (the amount of play) between the ring gear and the pinion gear. This is important to know so you can set the proper pinion bearing preload. ​

1. Install a dial indicator so that the tip of the indicator plunger is perpendicular to the drive side face of one of the ring gear teeth. The plunger should be in the valley between two of the teeth. ​

2. Grasp the pinion yoke to prevent it from turning. With the other hand, grab the ring gear and rock it, try not to let the pinion move. There should be a small amount of movement, you are not trying to move the ring gear a large amount, just rock it back and forth. Move the ring gear gear until it stops against the pinion gear. Zero the dial indicator. Move the ring gear back until it stops against the other side. This is the amount of "backlash" that is between the ring gear teeth and the pinion gear teeth. This gap allows oil to circulate between the gear sets to provide cooling. Measure the amount of the backlash. The backlash on this ring and pinion was : 0.006. Well within the preferred range for backlash. The following chart shows the differential specifications:​

Differential Specifications for GM 8/5" and 8.875" Ring gear​

Gear Backlash
Preferred 0.005-0.008 in.
Acceptable Range 0.003-0.010 in.​

Pinion Bearing Preload
New
8.5" 15-30 in.-lbs
8.875" 20-25 in.-lbs
Used
5-10 in.-lbs​

 

[398HBX]

Detroit TrueTrac Installed

I believe that I have the TrueTrac installed. The backlash is 0.005, the pinion preload is ~25 in.lbs ( I am assuming that the preload is the amount of force needed before the pinion will turn) It seems a little tight and it is harder to turn than before, but the specs say that it can go up to 30 in-lbs so I think I'm allright. Here are some pics of the gear pattern. I think the pattern is good. What say ye?


Drive Side


Coast Side

 

[Teck]

Nice build.
Pattern looks good but might be in just a little to much in the drive side. Hard to tell for sure in the pics.

 

[SUPER'BURB]

looking good!

 

[398HBX]

Front Axle Complete!

Well, I finally finished rebuilding my front axle. It was a ****load of fun! Of course, I had one of those "Oh-****!" momoents when I realized that I had forgot to put the snap-rings back on the axles. I'm just glad I remembered.

Here's what I did:

1. Relaced all bearings and seals.
2. Installed Detroit TrueTrac.
3. Relpaced all ball joints and tie rods.
4. Installed new Rancho steering stabilzer.
5. Installed new Rancho steering arm for 4" lift.
6. Replaced rotors.
7. Rebuilt calipers.
8. Replaced u-joints.
9. Cleaned and painted everything.









Now it's on to the rear axle.

 

[jt512]

Turned out great Now just think if you swap in a 60 down the road you get to do it all again

 

[398HBX]

Thanks! Yeah, but least I'll have a little bit of an idea what to do.

 

[magik235]

Extremely nice workmanship.

 

[shovelbill80]

i'm enjoying the hell out of your build.......one day i hope to do mine this way.......cheers