Frequently Asked Questions

Find answers to the most asked questions about your purchase, order or shipping

GEARS | SET UP - Should I use bearing grease on bearings during install?

Do NOT use bearing grease on your carrier bearings or pinion bearings when setting up your differential. This could cause premature failure from the oil not having the ability to lurbicate the bearings properly. Use clean gear oil only to pre-lubricate your bearings during the install.

GEARS | SPIDER GEARS - What is this whirring noise?

Whirring noise only while decelerating at any or all speeds is most likely caused by bad pinion bearings or loose pinion bearing preload, and almost never by bad ring and pinion gears.

A howl or whine during acceleration over a small or large speed range is usually caused by worn ring and pinion gears or improper gear set up.

Rumbling or whirring at speeds over about 20 mph can be caused by worn carrier bearings. The noise may change while turning.

Regular clunking every few feet may indicate broken ring or pinion gears.

Banging or clunking only on corners can be caused by broken spider gears, lack of sufficient positraction lubrication, or worn positraction clutches.

Rumble while turning may indicate bad wheel bearings.

A steady vibration that increases with the vehicle’s speed can be caused by worn u-joints or an out of balance driveshaft.

Clunking only when starting to move or getting on and off the gas might be loose yokes, bad u-joints or worn transfer case or transmission parts.

GEARS | CARRIER - How do I measure the preload on my carrier bearings?

It is nearly impossible to measure the preload on a carrier because it is in contact with the pinion at the time of assembly and therefore is receiving resistance from it as well. A carrier should have to be loaded in with some resistance, such as a few hits from a dead blow hammer. It should not simply load in by hand, and it should not take a huge amount of force to put into place.

GEARS | CARRIER - Are carrier bearing caps side specific?

Yes. The carrier bearing caps are bored at the factory and are side specific. Mixing up the carrier bearing caps can be a major mistake in rebuilding a differential, especially if it is a design which uses side adjusters. A good practice is to take a punch and mark one of the carrier bearing caps along with the side of the housing it belongs to in order to prevent mistakes during reassembly.

DRIVELINE | AXLES - What are the advantages of a bearing installation kit?

These kits are for shops and builders who have shims on-hand and are looking to save money over a Master Overhaul Kit. They include carrier bearings and races, pinion bearings and races, a pinion seal, marking compound, and a brush.