[edstruck]

I have owned, since new, and hope to keep, my 2010 Titan Pro-4x. Truck only has 105K miles and body and interior are great shape. I am having issues with road noise between 20-30 mph which gets louder until 60 or so when is uncomfortably noisy. At first I attributed the road noise to the tires (Toyo GT Open Country LT275/70R18), however, I finally crawled underneath to see what I could see. Much to my surprise there is a crack in the differential tube (not sure what to call it) that powers the passenger side wheel. The crack is on front and rear of casting right where it meets the flange. Diff is not leaking and 4WD works fine. Just changed the diff fluid and no metal particles were found, Appears the diff is OK except for the cracked tube. I am afraid if I continue to drive the truck the tube may break entirely and release the wheel and axle. Now, for the $2000.00+ question. What does everyone think re pulling the diff and having the casting welded? I believe it is aluminum so would have to have heli-arc weld done. There is an excellent welding shop near me and I trust their work. Would sure like to go that route rather than buying a new diff! Even a used one around here is about 1K plus shipping. Any thoughts greatly appreciated.

 

[busemans]

Wow. Did it get banged on something? As long as they can weld it so it's flush still since it s me to be a mating surface

 

[dubyam]

My take is you're asking for issues downrange having it welded. That's a tough request if even a very good welder.

 

[edstruck]

Its possible it happened jumping a curb head on too fast. My thoughts are to remove the diff and assess, then get opinion from welder. Hoping for option that allows a few more years without spending several thousand...

 

[edstruck]

Trying to detrmine front diff gear ratio for my 2010 titan pro-4x prior to purchasing a used front diff. My dealer could not give me an answer, however, parts counter guy entered my vin nbr and gave me the nissan part nbr for a new front diff (38500-8S11B) for my truck. Anyone out there know the gear ratio for this unit? BTW - new front diff from nissan $2366.41 before tax!

 

[dubyam]

When you drive 70mph on the highway, what is your engine RPM? If it's right at 2k, you have 3.36 gears. Down at 1750, you have 2.94 gears.

 

[edstruck]

Thanks, but diff is currently on the ground. I may crack case and count teeth if unable to verify by part number.

 

[dubyam]

Look on the snout of your rear diff for a white sticker. It will have a bar code and some numbers/letters on it. On that sticker (if it's still there and legible) the gear ratio is listed. Oddly, it's taken out to one additional significant digit, so instead of 3.36 it says 3.357 or some such.

If that doesn't work, teeth counts are the best option.

 

[edstruck]

No sticker on rear. Did find paper sticker on axle tube, but completely illegible. I checked thru my papers and did find window sticker and posted below.
Note under mechanical section on left it states 5 speed auto trans with 3.357:1 final gear ratio! I presume therefire both front and rear diffs have to be 3.357 gear ratio also?

 

[busemans]

yup. they have to be the same

 

[dubyam]

Yes, have to be the same.

 

[edstruck]

Just got call from dealer, he also confirmed 3.357! Now to find one! Thanks for all your help!!

 

[Hntndad]

In the meantime, since your front diff is “on the ground”. Pull the cv axles out, pull the transfer axle and drive it. See if your noise is gone.