Starting in about 1997 some Small and Full Size Ford Pick-ups began having water leak issues. Since then we have had so many people come into our Service Center inquiring about the problem we’ve taken the time to create this in depth page. Your vehicles problem is more than likely related to 1 or all 5 of the probable water leak issues we have seen in these trucks. Water flows onto and then down the cab so we'll start at the top and work our way down.
Ford's later designed back glassThese window units are fantastic in that we have seen no issues with them since they came to be in 1998.
* This is the most common leak for these vehicles *
If you decide to remove and replace your rear back glass window unit yourself be sure to use the proper pinchweld and window unit primers on both bonding surfaces as well as be sure to allow the proper flash times or you won't achieve a proper bond to one or both surfaces.
1. The plastic trim ring (expands and contracts) at a different rate than the window unit and the sheet metal cab causing it to tear loose.2. UV Rays from the sun will break down the adhesive in about 3 months, if you are lucky and it lasts that long, and then you will really have a mess on your hands.3. To make the vehicle right again you'll need a new window, a new trim ring, and a new 3rd brake light.
If it's in fact found to be the water is entering from the body seams on the roof.Do Not! apply any type of body seam sealer on them (no matter what it says in the directions on the tube) without painting a (UV Resistant) automotive top coat over the adhesive.If this isn't done the UV Rays from the sun will in fact break the adhesive down and it will roll right off in a very short time. We have seen this many times and it usually results in the vehicle needing to be repainted.
If your a DIY person here’s what NOT TO DO!
If you have a 1997/98 modelThere is a slight easily done modification required to the grey plastic trim ring in order for this window to be installed in it. There are two tabs that protrude down from the grey trim ring at the top of the window opening that must be removed.
Photos that show how to determine whether or not you have Ford’s early designed problem unit.
5.Water can be entering the cab though the back glass unit (itself) through small cracks in the plastic.Whatever type of material Ford used in this design certainly didn't make the cut quality wise that we are sure the designers had intended for them to have. We have also seen similar problems with some of the past era back glass units General motors put into service. The GM units we have seen were even worse in that when they cracked it created a gap sometimes as large as a 1/4 inch wide.This particular 1997 model Ford pick-up uses a poorly designed rear window (be it stationary or sliding) that had major issues.Ford shortly afterwards came out with a revised window that solved the problem.To our knowledge Ford did not actually recall these poorly designed window units, they just happened to replace them with a new and improved type of window unit with a totally different type of construction.If you have this type of unit installed in your vehicle (and it does in fact prove to be that the water is entering between the unit and the seal to the cab) unfortunately you are still looking at having to purchase a new window unit.The problem now is that the unit is installed with a bubble gum like adhesive called foam core butyl tape. This adhesive is extremely limber in that as you try and cut through it, it re-adheres to itself. In addition to that problem you cannot access the adhesive to cut it where the nine or so bolts go through the cab from the unit. All one can do is apply extreme outward pressure to the window unit and cut the adhesive as it allows access to it. What this does as a rule is that it flexes the window units brittle inner plastic frame causing, at best, small unseen micro cracks and at worst large gaping cracks.The bottom line is that reusing this type of unit no matter how good it looks after it's removed is not recommended. Even if the removal of the unit appears to have went well, the stress placed on the unit during the R&R procedure helps accelerate the plastic frames cracking process it does on its own.
4. Water can be entering the cab through the sealbetween the back glass unit and the vehicles pinchweld.
The pinchweld is actually constructed in two different layers. The layer on the outside is the one the window unit is actually bonded to. The outside pinchweld layer is attached to the second layer by spot welds.
3. Water can be entering the cab through a body seam. Once again make note that the pinchweld body seems also run up to the top corner of the cab under the plastic trim ring which could be where the water is entering.
If the trim ring mounting holes look ok, it may be that there is a body seem hole under the trim ring. The only way to absolutely find out is to R&R the trim ring which will require removing the window unit as it lays on top of the trim ring inner flange.
2. Water can be entering the cab through the grey plastic trim ring where one or more of the 16 foam gasket sealed alignment pins, clips and mounting bolts that attach it to the cab. It may be possible to seal the bolt hole by removing the nut, apply sealer to the hole and replace the nut.
1.Water can be entering the cab through the 3rd brake light gasket. We have seen several of these lights warped from heat producing an opening between the light and the gasket.