I posted in another thread in the 4th gen forum looking for advice on some faint whirring sounds I was hearing from what sounded like my rear end. I just bought this truck for a really good price used, and didn't anticipate I'd be already replacing something in less than a month. I have talked to a few auto techs I'm cool with and most said it sounded like my pinion bearing was on it's way out. The noise I hear is not really loud enough to be noticed with the AC blowing and radio on, but I can definitely hear it, especially when coasting / letting off the gas above 25mph. The thing is, it is not a constant whine/whirr like I have heard in other cars with bad rear diffs. It's only really slightly noticeable on deceleration.
So today, my buddy put it up on a lift, took a quick look at the "propeller" shaft and noted he was able to move it it around a little. Literally a few mm left to right / up down play. He took the driveshaft off, and looked at the pinion nut to make sure it was torqued and staked. He did not end up tightening this as we kinda ran out of free time. He did also drain the fluid and it was very dark brown/black with a good amount of silver gunk on the magnet. He added the correct amount of Mobil1 75w/90 and put it all back together.
I drove it around a bit and once it warmed up again, the noise was obviously still present, but seemed slightly quieter.
So should I:
1. Buy a master install kit and tear it down to find out what all has gone bad. He's basically telling me a poorly maintained truck with a bad pinion bearing could've led to wear on the gears, pinion, axle bearings (carrier bearings??) and anything else inside the 3rd. He said he can do it for me for a discounted rate but that it's time consuming and would require me being without my truck for a day or two while he gets everything sorted. Might end up costing about 400-500 dolllars, where as other quotes were as high as 2000 P&L.
2. Buy a complete 3rd from ecgs for like 650, send mine in, and start over with my new to me vehicle running as it should be for the foreseable future. He said he would actually remove and install the new one for 200 bucks if I helped him and because it's a lot less time consuming and would only take him 2 hours.
So - my only concern is that I might be replacing something that is probably not really even that bad off without even tearing it apart to find out - simply because it had a bad pinion bearing that may have caused wear on other components. To me it seems like a no brainer to at least look at everything to find out what other parts were affected. Most shops say they prefer to do rebuilds but it sounds like that's only because they can rake in 1000+ dollars in labor.
What would you recommend?
So today, my buddy put it up on a lift, took a quick look at the "propeller" shaft and noted he was able to move it it around a little. Literally a few mm left to right / up down play. He took the driveshaft off, and looked at the pinion nut to make sure it was torqued and staked. He did not end up tightening this as we kinda ran out of free time. He did also drain the fluid and it was very dark brown/black with a good amount of silver gunk on the magnet. He added the correct amount of Mobil1 75w/90 and put it all back together.
I drove it around a bit and once it warmed up again, the noise was obviously still present, but seemed slightly quieter.
So should I:
1. Buy a master install kit and tear it down to find out what all has gone bad. He's basically telling me a poorly maintained truck with a bad pinion bearing could've led to wear on the gears, pinion, axle bearings (carrier bearings??) and anything else inside the 3rd. He said he can do it for me for a discounted rate but that it's time consuming and would require me being without my truck for a day or two while he gets everything sorted. Might end up costing about 400-500 dolllars, where as other quotes were as high as 2000 P&L.
2. Buy a complete 3rd from ecgs for like 650, send mine in, and start over with my new to me vehicle running as it should be for the foreseable future. He said he would actually remove and install the new one for 200 bucks if I helped him and because it's a lot less time consuming and would only take him 2 hours.
So - my only concern is that I might be replacing something that is probably not really even that bad off without even tearing it apart to find out - simply because it had a bad pinion bearing that may have caused wear on other components. To me it seems like a no brainer to at least look at everything to find out what other parts were affected. Most shops say they prefer to do rebuilds but it sounds like that's only because they can rake in 1000+ dollars in labor.
What would you recommend?
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