Re: Wich aftermarket front axle do you recomend?
ummm this says UTAH is correct on the TJ:
Wrangler Dana 30
The YJ and the TJ don't use locking hubs. The YJ uses a troublesome vacuum actuated axle disconnect system. The TJ uses high quality bearings that have very low resistence so it doesn't use hubs or an axle disconnect system. Wranglers use and smaller rotor than the CJ. The TJ also uses a different pinion from the YJ. The TJ pinion uses a crush sleeve instead of shims. This difference made gear R&P selection for the TJ a bit limited at first.
CJ Normal cut Dana 30
YJ Reverse cut Dana 30
A strength of the YJ Dana 30 is its use of reverse cut ring and pinion. The ring and pinion are stronger when they are reverse cut in front axles. The reverse cut axle also provides better ground clearance and driveline angles.
Unfortunately, the TJ does not use the reverse cut Dana 30. It uses a normal cut Dana 30 similar, but not compatible to, the CJ Dana 30.
The YJ Dana 30 uses an axle disconnect system that is prone to failure. Often the vacuum hoses the activate the disconnect system will fall off or tear. Sometimes the vacuum motor won't have enough power to engage the sleeve when the gear lube in the disconnect housing gets gummed up. Another problem is that since only one axle is ever disconnected, an automatic locker or limited slip differential can cause problems with the axle and with handling. The drivers side axle is always spinning the differential.
. The TJ has done away with with the system completely which is good in that it is not likely to fail, but since there is no way to stop the differential from spinning, an automatic locker or limited slimp can degrade handling on the road.
The YJ and the TJ Dana 30 uses the 5 on 4.5" wheel bolt pattern. The YJ Dana 30 is of course set up for leaf springs and the TJ Dana 30 is set up for coil springs.
Comanche, Cherokee, and Grand Cherokee Dana 30
The Comanche (MJ) and Cherokee (XJ) use a reverse cut Dana 30 and the Grand Cherokee (ZJ) uses a normal cut Dana 30. Like the YJ and the TJ, these axles use a 5 on 4.5" wheel bolt pattern. All of these trucks use coil springs up front.
The Dana 30 front axle was used for a short time from 1971-1973 in Cherokees (SJ), Wagoneers (SJ), and J-Series pickups.
Other Dana 30 Information
Here are some other articles related to the Dana 30. Dana 30 Disk Brake Conversion: How to convert a drum brake Dana 30 to disk brakes. Some minor Dana 30 differences are documented in this article including differences in spindles, bearings, and brake hubs. This article also explains why the Dana 30 is a good low buck axle upgrade for '45-'71 CJs