MTCFORUM
02-13-2002, 09:19 PM
Before I can even go into all this stuff, I need to give some history and some term definition.
The name for the Mark 8 chassis, within Ford, is called an FN-10 and a T-Bird is a MN-12 (from 1989-1997). As I'm sure you know the chassis are almost identical. If I use one term, like FN-10, I mean both chassis unless I specify otherwise that my comment is just for one of them.
The FN-10/MN-12 chassis is very, very prone to driveline vibration due to it's body structure. Body structure is the rigidity of the body and chassis. This lack of body structure is one of the reasons why these cars no longer exist today. There are some other reasons that I'll get into one day in the future.
Now, by lack of body structure I mean that the body itself is not stiff enough. This means that it is very suspectible to flexing. This poor body structure leads to NVH problems. NVH is Noise, Vibration, and Harshness. Noise and vibration should be easy to understand, harshness can be things like impact harshness going over bumps and things like that.
Now, in typical Ford fashion, the first year of new car, no expense is spared and all the good stuff is put in there to make the car right. Then the &^$* bean counters come along and say the car is not profitable enough and start to take out the good stuff that in's there. What I mean by this are things that are subtle that they can do to impove the body structure. Things like thicker mastic on the floor pans, structural foam in the rockers to stiffen up the car. While these are all band aid's for bad body structure, they are effective band aid's. The original Marks in '93 had this stuff, but it was quickly thrifted out by bean counters and complaining by the assembly plants that it was too hard to build.
So, with that foundation, I have decided to make a seperate post on the actual cause of the vibration. This is just a history.
jerry
The name for the Mark 8 chassis, within Ford, is called an FN-10 and a T-Bird is a MN-12 (from 1989-1997). As I'm sure you know the chassis are almost identical. If I use one term, like FN-10, I mean both chassis unless I specify otherwise that my comment is just for one of them.
The FN-10/MN-12 chassis is very, very prone to driveline vibration due to it's body structure. Body structure is the rigidity of the body and chassis. This lack of body structure is one of the reasons why these cars no longer exist today. There are some other reasons that I'll get into one day in the future.
Now, by lack of body structure I mean that the body itself is not stiff enough. This means that it is very suspectible to flexing. This poor body structure leads to NVH problems. NVH is Noise, Vibration, and Harshness. Noise and vibration should be easy to understand, harshness can be things like impact harshness going over bumps and things like that.
Now, in typical Ford fashion, the first year of new car, no expense is spared and all the good stuff is put in there to make the car right. Then the &^$* bean counters come along and say the car is not profitable enough and start to take out the good stuff that in's there. What I mean by this are things that are subtle that they can do to impove the body structure. Things like thicker mastic on the floor pans, structural foam in the rockers to stiffen up the car. While these are all band aid's for bad body structure, they are effective band aid's. The original Marks in '93 had this stuff, but it was quickly thrifted out by bean counters and complaining by the assembly plants that it was too hard to build.
So, with that foundation, I have decided to make a seperate post on the actual cause of the vibration. This is just a history.
jerry