I'm not sure what exactly you mean about your seats being uncomfortable? So, I'll let you know about my experience with my '03 3500, 4X4, SLT, Quadcab. After a number of years, I found that I could only drive about an hour or slightly more and then my right thigh would start to ache and I would have to stop, get out and walk it out. Either I was noticing a pinched nerve or blockage of blood causing pain and a kind of numbness. As I was not getting any younger, I thought I was having a physical problem and was worried. So, I started researching the subject on the TDR and, fortunately, found I wasn't the only one having this problem. Actually, one member came up with a clever fix for the problem and it included new foam for the seat.
I live in the Phoenix area and found an automotive upholstery warehouse in the Tempe area and went there for advice. The man that owned the warehouse asked if he could look at my truck and crawled on the floor and looked under the seat and came up with a fix that has worked beautifully for me for many years.
He told me that the original foam on the seat was collapsing and after driving for an hour or more, I was actually sitting on a metal gridwork called a "ladder", which, was the framework that supported the foam and upholstery and acted like a spring, also. That metal was pressing on my leg and causing the discomfort.
Basically, what he recommended was to place additional 1/2" thick CLOSED CELL FOAM in the seat area. Also, he recommended and sold me a carpet sample for both front seats.
What you do is place the carpet sample, bottom side down (burlap) on the ladder. The carpet sample gave a lot of support so the new foam would not collapse around the ladder wires. Then, you cut and install the 1/2" CLOSED CELL FOAM on top of the carpet sample. CLOSED CELL FOAM is very similar to foam pads found in gymnasiums used for wrestling, tumbling etc. and anywhere you don't want to fall on hard flooring. It's not thick but absorbs a lot of shock. The foam is a lot thinner but, works extremely well for what I needed it to do.
I put the seats covering and original foam back together. The only thing I noticed was a slight bulge in the seats. It is not at all uncomfortable and now I don't even see the bulge but, I sure do notice the difference in comfort!!!!
I've spent at least one summer on the road with my travel trailer & have gone as far east as Charleston, WV. and Toronto, ON. Canada spending from early morning until later in the evening, driving, and have never once had the pain in my leg since doing this fix. It really worked well for me!!! One haul was from the WV.-KY. border to Topeka, KS. in a day (around 900 miles, if memory serves me right).
The thing that makes me mad is that the engineers at Dodge were unable to make a comfortable seat for this truck. They have been making trucks for over 100 years and 'still' were unable to create a comfortable seat. I've never designed or built an automotive seat in my life!!! I've been a dental technician for nearly 50 years but, I was able to fix my problem with very little cost and the help of a member on the TDR giving me the idea. I just modified it with the help of the owner of the upholstery warehouse. All those engineer's should have been forced to ride across the country sitting in one of their creations!!!! My guess is they would go back to their drawing boards and put a little more effort in their seat design's!!!!
I've written about my "fix" numerous times and my posts can probably be found in a search if you want more information. I hope this information helps you fix an uncomfortable situation if this is the problem you are having.
I don't remember just how much it cost but, I think it was under $20.00 and I still have enough CLOSED CELL FOAM to do a couple more seats. Again, I've never had the same problem since doing this modification. Good Luck with your problem!!!
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