It could be a combination of wires and the amp, but I would start with the amp.
In the 1997 - 2001 Cherokee the front door speakers are 6.5 inch. However they do not match 6.5 inch aftermarket speakers.
1998 Jeep Grand Cherokee Sport Utility without Infinity system Factory Stereo Installed [change] Factory replacement info: In-dash stereo 8-1/8" depth; Size code CG,E,GC Front speakers Dash: Tweeter factory speaker note Front Door: 6-3/4" Rear speakers Rear Door: 6-3/4"
The front speakers are 5 1/4"
Front speakers Front Door: 6-3/4" factory speaker note Far rear speakers Rear Pillar: 4x6" factory speaker note
The front and front door speakers on the 1993 Jeep Grand Cherokee are 6-3/4 inches. The rear and back door speakers are also 6-3/4 inches.
My 1992 had 6" Factory Round speakers in the front doors and 6 X 8 Factory speakers in the back. My 1998 has Factory 6X 8 speakers in the back (extended cab) and haven't checked the front ones yet. my 1994 has 6"x8" as well in the front and rear.
6.5 Speakers both in-front and rear
They are 5.25"
5.25" front and rear sound bar
All four are 6 inch.
Check your EQ System, (The CD player) if the balance is in the middle
The front axle did not have limited slip from the factory.