Dana/Spicer Co.
They manufacture differentials for trucks and off road vehicles. Diffs come in different sizes according to application. The smaller the number of splines, the weaker it is. Jeeps come with 30,35 or very few 44's. To get a factory TJ with 44's in it is a score! If you want a 60, you usually have to upgrade after you get your vehicle. 30 and 35's are usually sufficient for light 4 wheeling. 44's are strong enough for my Jeep. I am not a crazy rock racer or anything like that. I did break 2 30's when I had my Cherokee, but haven't had any breakage with my 44's.
They manufacture differentials for trucks and off road vehicles. Diffs come in different sizes according to application. The smaller the number of splines, the weaker it is. Jeeps come with 30,35 or very few 44's. To get a factory TJ with 44's in it is a score! If you want a 60, you usually have to upgrade after you get your vehicle. 30 and 35's are usually sufficient for light 4 wheeling. 44's are strong enough for my Jeep. I am not a crazy rock racer or anything like that. I did break 2 30's when I had my Cherokee, but haven't had any breakage with my 44's.