Off Roading Forums banner
1 - 5 of 5 Posts

· Registered
Joined
·
59 Posts
Discussion Starter · #1 ·
What did I break?

2001 GMC Yuknon 5.3L 4L60E ?NP246?

Symptom:
2wd no problems, 4wd (high or low) no problems; 4wd (high or low) turning or giving it significant gas it sounds like a snare drum from under my truck.

Whats been done:
Tranny rebuilt (by shop)
X-fer rebuilt (by shop)
U-Joints replaced (by me)
Rear diff rebuilt (by me)
Front diff rebuilt - with new electronic selector (by me)

any ideas on where to look? I can post vids later if requested...
 

· Registered
Joined
·
59 Posts
Discussion Starter · #2 ·
I cannot dial in the location from with/in the cab. I have had others listen from outside of cab when I make it make its noise, they seem to think it is from around the x-fer.

Below is more specifics as to what was done to the components to the best of my ability... listed by time kinda.

The rear end was tore down and a posi was installed with new ring/pinion as well as seals and bearings. (After this mod I believe I did not have the noise) While rhomping (After noise started) I twisted an axle, and did a field rebuild (new axle and major cleaning) when I got home I tore down the rear end and cleaned it and put new bearings and seals in with/ same ring/pinion and posi (noise still present).

Got a rebuild tranny (with shift kit) from AAMCO when on vacation in Cali. A bit later while taking off (normally) from a red light lost a planetary gear (I do not know trannys well so I cannot be more specific at this time)

I replaced the u-joints w/grease-able after markets (not sure of brand tight now) from Napa (Noise still present)

Took Xfer case to a shop (local no-name) and they said there was nothing wrong with it; took Xfer case to AAMCO (different location) and had them look at it due to leaking (they had to remove it to put in the tranny so they would cover any seals they had to break during tranny install). They noticed I had wore a hole thru the case from the pump shifting. They replaced the half of case and installed what they call a case saver. I had also mentioned the noise to them at this time so they "tore the case down and rebuilt it but did not see anything wrong" (Noise still present). They suggested it was in the front diff.

I scored a different diff and got all new seals, every bearing (carrier and shaft), and new electrical selector. I tore down the front diff and found nothing wrong with the gears (no ware or missing teeth). I used the same ring/pinion that came with the new to me diff and put it all together. (Noise still present)

I then had a rear seal leak so a few weeks later I took it back for that and had them check the transfer case again for what could be making the noise; they supposedly replaced the rear seal (still leaking) and had the main mechanic look at the gears and reported no issues found.

They think it was my front diff and rear diff having different ratios. I took pictures of the front ring/pinion and confirmed it was 3.73; so I took the lid off the rear diff and 3.73 is on the ring gear and I counted and math'ed out 3.73 as well.

the above is close to the timing and what was done; once again sorry for not every specific captured but near the beginning of this I was not thinking it was going to kick my @$$ so hard.
 

· Registered
Joined
·
59 Posts
Discussion Starter · #4 ·
I already replaced the driver side and inspected the passenger side; I will check it again. You think I spun the splines on the half shaft or the massive knuckle setup for the outer angle change?? It bolts directly to the wheel hub, I can have someone watch the outside nut and try to gopro the shafts while I make the truck cry out in pain :grin:
 
1 - 5 of 5 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top