Driveline gurus need your help

[flyinz11]

My 89 Blazer has a horrible noise that we can't quite isolate. The conditions are: interstate speeds (70 or so) for 10 or more minutes. After I slow down/stop and start to take off again there is a horrible sound like maybe something in the driveline is binding for a spilt second and releasing creating a loud metal clunking noise. It happens a few times after going again then stops. It never happens when driving in town.

I have had the transfer case, transmission, and rear end looked at be a local shop with no hint of problem. I pulled the front diff cover off tonite and it looks good as well. Clean oil, no metal flakes.

I can only conclude that the hubs are somehow "catching" as they get hot(they do get hot, is this normal?) They are the stock hubs. I have 254,000 miles on the truck...everything is original except the engine which I swapped out 10 months ago.

Sorry for the long post but this should cause one of you guys to sayh yeah...been there done that!!


1989 K Blazer
Warn M12000/Enforcer Bumper
32's
254,000 Miles and still going!!

 

[Blazer_Boy]

Can't really give concreate help here but there ain't nothing to check your hubs. Undo all those allen screws and take out the guts and put in a manual lock-out. Probably isnt the prob but they're better than autos.

<a target="_blank" href=http://www.geocities.com/bigkern76>http://www.geocities.com/bigkern76</a>

 

[wayne]

I would check the rear axle again and look at the spider gears real good. Also you might want to put new u-joints in the rear shaft if they have that many miles on them. I don't think the hubs getting hot is a good thing either. On my 89 when I had the stock auto hubs they never got what I would consider hot.

See <a target="_blank" href=http://coloradok5.com/gallery/Waynes-Toy>Project Mighty Mouse</a> here.
<font color=blue>Wayne<font color=blue>
<font color=blue>Happy Trails<font color=blue>

 

[backlash]

It is pretty amazing, the amount of havoc the auto hubs can make when they go out! I didn't believe the symptoms I had and you have could cause the clunk/bind at take off.

I really liked the idea of having auto hubs ... but I finally gave in, changed them and never looked back. Not saying this is your problem, but it sure was mine ... and is an easy fix!

I ended up pulling my auto hub on the affected side, covering the opening well with duct tape and driving it like that till my ordered hubs came in.

Good luck!

 

[Espen88k5]

Hi
I still have auto-hubs as well. I drove 14 hours pretty much straight last month, and I checked around the truck at every short stop I made. I always touched the front hub's and they where always cool.
Take it apart and see if it's in need of a litle grease. If you havent yet, buy the Haynes manual, it has good pictures of the hub assembly.(somebody here has a scan of it to, if I remember correctly)
Also here is a link to some pic's I took when I had mine apart:
<a target="_blank" href=http://:http://www.eurofoto.no/fotoalbum.ph...in=eurofoto_default&amp;portal_language=nn_NO
>:http://www.eurofoto.no/fotoalbum.ph...in=eurofoto_default&amp;portal_language=nn_NO
</a>
password is : dana


&lt;P ID="edit"&gt;&lt;FONT class="small"&gt;&lt;EM&gt;Edited by Espen88k5 on 10/25/01 12:43 AM.&lt;/EM&gt;&lt;/FONT&gt;&lt;/P&gt;<P ID="edit"><FONT class="small">Edited by Espen88k5 on 10/25/01 12:44 AM.</FONT></P>

 

[flyinz11]

I pulled both hub caps off and didn't see any obvious signs of damage or any metal shavings. Thet look like they could use a little grease. Since they get hot and the front end (hubs) does weird things when you rotate the yoke i am going to go ahead and thry the Wark premium hubs on there and see if that does the trick. Thanks for the help!

1989 K Blazer
Warn M12000/Enforcer Bumper
32's
254,000 Miles and still going!!

 

[flyinz11]

I pulled both hub caps off and didn't see any obvious signs of damage or any metal shavings. Thet look like they could use a little grease. Since they get hot and the front end (hubs) does weird things when you rotate the yoke I am going to go ahead and try the Warn premium hubs on there and see if that does the trick. Thanks for the help!

1989 K Blazer
Warn M12000/Enforcer Bumper
32's
254,000 Miles and still going!!

 

[Rob 85K5]

Here are pics of the hub and a front 10 bolt

<a target="_blank" href=http://wsphotofews.excite.com/012/CI/3P/JO/K186344.jpg>Hub Exploded View</a>

<a target="_blank" href=http://wsphotofews.excite.com/025/5u/BT/xs/Po96259.jpg>Front 10 Bolt Exploded View</a>

Rob 85K5

<font color=orange>Bleedin' Chevy Orange</font color=orange>

 

[extremeblazer]

My truck does the same thing. A local GM truck place told me that the splines on the output shaft of the t-case wear and the only fix is to replace it. They also said to pack it full of grease. An old time GM tech told me that some of the driveshafts were made a little too long and have to be machined down. Both fixes seemed too expensive so i just live w/ it.