I have a Jeep Liberty 3.7L. I noticed a few months back I started having a strange exhaust smell after putting some pressure on the engine. Like when I drive up hill and stop at a guard post to get on base is at a 45 degree incline. Then a few yards later I am level again and I get the exhaust smell coming from my A/C. I'd also note I had to go through a lot of deep pot holes to get to parking on base nearly every day. However, today I was driving and my transmission light came on. for the past couple weeks I noticed a slight squeaking sound when I go into reverse and when making turns when I first start driving. I checked my fluids. Oils really low and needs changed, but the transmission fluid is good and so is my coolant. What do you think it could be?