- 150
- 37
- 28
- Location
- Burtonsville, MD.
I have a 1986 M998 that was overhauled in 2007 in ME. I noticed on the diff cover tags that the rear is stamped 2.56 and the front is stamped 2.73. I was going to pull the covers today with the vehicle on a lift until I discovered the brake caliper mounting bracket is blocking access to one or more of the cover bolts so I marked the pinion yokes and half shafts and had someone hold one wheel while someone else watched the drive shaft while I spun the other wheel. We tried this various ways and came up with the same results. I was hoping someone put the wrong tag on one of the covers but it is clear that one pinion yoke turns more than the other with 1 revolution of a half shaft. Has anyone else seen this where they have mismatched differential ratios? I have not noticed any binding but I also have not driven on pavement in high lock mode. The HMMWV has the NP218 transfer case which I have been told by various sources does not use clutches in the transfer case like the 242 models do. I have driven Jeeps with mismatched ratios with wider spreads in the ratios and in 4x4 mode they made terrible popping sounds from the transfer case