Recently I purchased a Riddler cover for my Chrysler 8.25 rear differential. Below are my experiences with it so far.
1) This thing is a beast, if I ever crack it I'm guessing I won't live to know about it.
2) I had an in depth conversation with a gentleman at Riddler this morning, and he was very helpful and great to work with. Finding his phone number was not so easy, I actually found it at the bottom of a review elsewhere.
3) It comes with grade 5 bolts, same as the stock. They are just longer due to the cover's thickness. They should be torqued to approximately 13 ft-lbs (dry) according to SAE. The gentleman at Riddler confirmed this. This is not a problem unless you use a LubeLocker gasket, which specifies 35 ft-lbs. 35 ft-lbs will break the bolts like it did on mine. I decided to get new grade 8 bolts, torque them to 25 ft-lbs (SAE spec) and I assume that it will be enough for the gasket. Others have stated that they had no leaks at this amount of torque. So far I don't either. If you are replacing the bolts, get 5/16-18 grade 8 bolts, 7/8" long. I used 1" and had to cut off 1/8" after they proved slightly too long. 3/4 long might be ok but I think you'd only get 3-4 threads in. The riddler cover comes with 7/8" bolts, but they are grade 5. Again, grade 5 is fine unless you are using the LubeLocker gasket. My 1" grade 8 bolts and lock washers were a total of $1.40 at tractor supply company. They had a good selection of bolts there.
4) If you fill the differential to the cover fill hole on a stock Liberty, you'll be overfilling it as I did. It accepted a little over 3.5 (!) quarts of gear oil. Today the gentleman told me that I need about a cup more than the stock recommended amount which equals a total of about 2.5 quarts. He told me the level should remain the same as the stock level for the gears, the cover itself just holds slightly more oil. They put the fill hole higher to aid in the filling of rotated axles. If you have not rotated your axle to improve pinion angle after lifting, you should watch how high you fill this. My plan is to remove a quart of oil from it with a siphon and make a dipstick out if a piece of wire, marking the level. I'll use that to check the level periodically.
Final Thoughts
Obviously I'm not an expert on this
, but I thought my experience this weekend and my phone conversation with Riddler might be of some use to some of you down the road. A cautionary tale, if you will. I think this is a great differential cover. I only wished I knew then what I know now, and I wouldn't have blown my weekend jacking around with this thing. If I were to install for someone else, I'd have the right bolts on hand, would use 25 ft-lbs to tighten, and would put in 2.5 quarts of gear oil. I'm guessing this would take about an hour, two or so if you're taking your time / drinking beer / enjoying yourself.
