Hey all
I just recently acquired this Blazer and it has a really nasty vibration from around 40mph, and has a nasty loud grinding kind of noise upon taking foot off pedal above 35-40... (power braking to slow down without taking foot off pedal seems to greatly reduce the noise) naturally, that's hard on brakes, but I'm just trying to figure this particular problem out

I am thinking it might have something to do with the front driveline angle from the lift... (8" suspension) I didn't install lift, it came this way...

attached are a few pics, was wondering if someone would be able to tell me if the driveline angle seems too steep... (especially coming out of the transfer case... is appears real harsh to me, but I don't know what "too steep" would be)

thanks in advance for any help!

 

What does the truck have for a transfer case? From the looks of it, it is the NP208 so the front driveshaft should not really be turning when in 2HI unless the lock-out hubs were locked in. You should be able to spin the front driveshaft when in 2HI. I cannot tell if you have manual (reliable) hubs or automatic (unreliable) hubs.

The lift looks like it included spacers to drop the transfer case which has caused the front output to tilt up in the air making for some really bad angles on the CV joint at the t-case on the front output.

 

Thanks for the reply!!!!!

I'm not sure of which transfer case it is, haven't really spent a lot of time looking under it... (it's bitter cold here right now, and it doesnt fit in my garage )

it doesn't have manual hubs (I wish it did) - so I was assuming it was the "full time" hubs, which are basically always locked? - you mentioned "automatic" was there something in these years where it would disengage the hubs automatically? - or how can I tell?

So, with the angle being bad on the front of the transfer case, what can I do to fix that? (less lift is not an option, I like big lifts )

 

Dropping the transfer case mount is a cheap and bad way to attempt to correct the driveline angles. I would remove the spacers to put the transfer case back up in the proper orientation and then look into some new driveshafts. High Angle Driveline makes some phenomenal shafts and can help to get your bad vibrations under control.

If the rear driveshaft is ok with the mount returned to its stock location, you may be able to get a clocking ring to rotate the transfer case down to get a better angle at the front.

In your second picture, you can see that the front output is actually pointing up where the CV joint then gets it pointed in the other direction.

For the time being, I would either remove the front driveshaft, or ditch the auto hubs and replace them with a set of warn premium manual hubs.

 

makes sense... I was wanting manual hubs anyway for mileage reasons... I tried a bit of searching, and found all kinda of weird stuff for that... would a place like Summit carry those? - and what would the difficulty level be of installing the manual hubs?

 

Not sure if Summit carries them, but many local places should. There really isn't much to it. There should be many tutorials on the net to read through. I have to get the crappy hubs off my K5 and put a set of Warn Premiums on at some point. One of mine doesn't like to lock in some times. I have to hit it with a rubber mallet to get it in every once in a while.

 

ok, so it's not a major week long project or anything like that then!? awesome!

Thank you very much for your help, I thought the angle looked bad but wasn't sure... figured it'd be best to ask!

Thanks again!

 

It shouldn't take more than 15-30 minutes per wheel depending on your experience level. You will need snap ring pliers and some smaller allen wrenches, but other than that, no real special tooling.

 

very cool, that'd be great, then I could leave hubs out all summer long too...

this appears to be what I'd need, anything this is missing?

http://www.amazon.com/Warn-20990-Pre.../dp/B000182DYC

thanks!!!!!!!!

 

Yes, that is the proper conversion hub. It also looks like you may need to converter the spindle nut over as well. The amazon link shows the conversion spindle nut as well as the socket to remove the spindle nut. The note from Warn's website states "When Replacing Automatic 3 Hole Cap Screw Hubs, You Must Purchase Corresponding Spindle Nut Conversion Kit"