Trailmaster Inversion
The Trailmaster second strut mount "Inversion Mod"
http://www.nwtoys.com
As many of us with the Trailmaster lift have discovered, it's a great lift, but the stock second strut is worthless. The TM struts are waaaaay over priced and they blow out in as little as an hour after installing them. Many of us who have lived through the second struts failing give advice to people to not even install the stock struts. Instead, throw them as far as your arm will allow.
The fix is to install Gabriel (Part #G44774) or the Bilstein's that have recently been discussed. Unfortunately, the installation normally requires that you do some custom grinding to the struts before you install them, because they lack the "shoulder" of the stock TM struts. This can be done at home on a bench grinder or by a machine shop for a more finished appearance, but it remains an extra step in the replacement process.
Update 07/20/2003: Rumor has it that Gabriel has renumbered their parts and the G44774 number no longer works. The story is that the new number is "G46720". I have not yet verified this yet. The strut is normally used for the front end of a VW Jetta, so if the first number doesn't work, try the second number. If it's for a Jetta, then the stories are true :) (Strut Gabriel G44774 (For 91 VW Jetta))
Add to this that in stock configuration, the second strut limits the down travel of the suspension, so at full extension, there is often a nasty clunk as the second strut "tops out". To counter this, I tried a set of 2.5" second strut spacers. Those improved my travel by just over an inch, but they changed the geometry such that the collar on the strut impacted the TM tower as well as making it such that the struts now bottomed out with an even worse bang when the suspension was fully compressed. The one run I did with them installed was a miserable experience, full of horrible, unidentifiable noises :(
On top of all that, is that it's a major pain to tighten down the bolt that holds the strut into the mount when the mount and strut are in position. Without a body lift, it's almost impossible.
So, in a major bout of frustration spawned brainstorming, ChrisCo and I put our heads together in the WATTORA garage and noticed that the second strut mount could be inverted to gain about an inch of travel and could be modified to allow the Gabriel struts to be used without grinding. The best of both worlds. Since the mount is assembled to the strut off the truck, you can easily torque down the top mount nut too :)
As will all mods, you must determine the suitability of this one for your application. It's working great for me and others I have spoken with, but since I don't know you or your truck, you need to be smart about whether the mod is for you and your rig :)
-Rob (WATRD)
Here's a shot of a Gabriel strut and of a Gabriel strut ground down for use without the inversion mod.
And a shot of my rig with the second strut removed. You will likely want to tie up the part of the second strut mount that is attached to the knuckle to prevent over extension of the axle. Note the white twine tying it up in this example.
Once we had removed the strut, we removed the upper mount, held to the TM tower by three short bolts. To allow the use of the Gabriel replacement struts without grinding them, you will need to grind down the metal center collar of the mount until it is flush with the rubber. Don't forget to do both sides of the mount.
We also found that the rear most mounting ear on the mount came into contact with the back of the TM tower. So, we clearanced it just a bit. You can test this by test fitting the mount back up into the tower from the bottom. The original configuration had the part of the mount that protrudes the most, facing downward through the tower hole. You will be inserting it from the bottom, with that part sticking UP through the same hole.
Here's a shot of the clearanced ear. Make sure you get the right one. one ear is obviously different from the other two. That is the one.
And a shot of the mount in the inverted position. Note the way the washer in the picture sits down flat on the rubber mount. That is a sure sign you have removed enough of the metal sleeve in the mount.
Next, you need some new washers. Then need to be sized such that the inner hole allows the strut to fit through it like this;
AND they need to sit flat on the surface of the rubber part of the TM like this;
The washers I used are a bit less than 1/8" thick and are pretty solid.
Next comes the assembly. Stand the strut up, in the position it operates in. Note: DO NOT forget to put the upper strut enclosure over the strut before you begin assembly or you will have to do this all over again.
Now drop one of your new washers over the threads.
Next comes the mount.
Another washer;
A bit of blue Locktite;
and the top nut;
Then use your handy impact wrench to seat the nut.
Here's a shot of the final assembly. Note that the nut still does not come all the way down, but the Locktite seems to be holding just fine after about 5000 miles...
Then it's all over but the reassembly. The TM instructions tell you to put a shot of motor oil into the lower strut housing, but I prefer a liberal wad of a good, waterproof bearing grease. It seems to last longer and is not nearly so nasty to clean up the next time you have to take it apart. Be sure to put a wad into both the upper and the lower strut housing.
Here's a shot of it all greased up and ready for install...
Drop the strut into the lower housing
Then as it expands, align the upper bolt holes and mount with the tower. The ear you ground faces back toward the engine.
Here's a shot of ChrisCo tightening the mount bolts back into place.
Next, use the bolts that connect the upper housing to the lower housing to pull the upper housing down onto the lower housing, inserting the alignment collar along the way...
Install the back plate and the four bolts holding it and you are done with this side. Enjoy!
-Rob (WATRD)