jonbar87

Had a set of Nitro 4.56 gears installed yesterday. Everything seemed to go well and I followed the break in procedures they recommended of pulling over every 30 minutes to let them cool down completely before starting again. Today I decided to check the dipstick to see how many shavings were on it and noticed that the fluid was only about 1/4 inch up the dipstick. There is also a noticeable whine on deceleration. I only hear it on deceleration though; sounds completely normal when accelerating. From my experience, whine on deceleration means incorrect backlash. I hope I'm wrong though.

1. Anyone have any experience with new differential noises? I hope it's just normal and part of the break in process.

2. Is it necessary to fill the oil up to the full mark on the dipstick with these Mag-Hytec diff covers? I assume so, but ECGS are some pretty reputable guys so I thought maybe there was a reason they didn't...

nickel_work87

Yea I would think so be use if it's that low there is not enough out getting to everything. I would drain it and flush all that metal out and refill with the correct amount of diff fluid. Plus the wear oil as well.

jonbar87

I'm thinking about doing that. I emailed ECGS and am waiting for a response before I do anything. I want to hear what they have to say...

nickel_work87

Ok sounds like a winner. What I looks like they did they just put the stock amount of fluid in there and did not accommodate for the bigger cover. i think that cover holds 3 to 4 more quarts than stock.

jonbar87

I think so too. Yeah it holds 2.25 extra quarts of oil (5 Total). What's odd is they charged me for 6 quarts of gear lube though...

winchested

So go back and take the mechanic on a test drive?

They must warranty their work?

jonbar87

They do, and I plan to. It just sucks cause it's an hour drive up there

Lethal Weapon

I would definitely drive down to them & have them check it out. The fluid should be full, no matter what size cover you have. (It's possible they only filled it from the OEM plug on the differential itself). Once it's full, it comes out of the same opening.... But if they did not fill it from your new diff cover, that may explain the low fluid. On the gears.... A whine is not good to have at all. ... There is a "drive" side & also a "coast" side of the teeth of both the ring gear & also the pinion gear. If the tolerances are "too tight or too loose" that can also cause the whine.

There are shims used on the carrier bearings for the "side to side" tolerances, and also shims for the pinion for the "in & out" so to speak. All these shims are thin (thousandths of an inch increments) and it's a tedious job to get the pattern just right. Can get more technical, but I think you get the idea. If the pattern is not correct, you will get a whine, or hopefully they did not hurt any of the bearings in the process???? Let us know on the results, but definitely get it rectified soon.
Also keep us posted on the overall performance on the 4.56 gears. I'm sure you it brings a lot of the power back.

jonbar87

Great info, thanks. Yeah I knew it's a tedious job which is why I paid to have it done. Anything else and I would have done it myself.

So far I really like the extra power. It doesn't even feel like I have 35s which is exactly what I was looking for. Now to just get this whole whine noise issue resolved....I swear I have the worst luck.

Gonkey

Just put gears in my truck with Mag cover and had to put extra 2 qts to fill. Gear noises and shavings are not good . Would definitely get in touch with installer right away and ask b4 you change fluid to proper level ( loophole to blame customer ). I am guessing pinion preload or coast pattern is off. I am also interested to see if gearset is actually 2010 or earlier with conversion bearing ? Hope it works out .