After the 5 speed swap I had a vibration on hard acceleration at around 3k rpm... aka about when the secondaries kick in. Kind of a wild goose chase on a truck that set for almost a year. I checked fuel filters, fuel pressure, took the fuel pressure regulator out that I added while it was down. Changed plugs, checked just about everything.
Eating at me in the back of my mind was the fact that it seemed like the trans sat a light higher than the A4LD/C5 did on the crossmember, like the trans was thicker between the output shaft and where the trans mount goes. I checked the angles and everything checked out at the time though.
Well the springs were weird, maybe it is spring wrap combined with the weak springs. So I did the rear suspension upgrade. It helped with accel but now I had a light vibe at highway cruising speed. Loosing ground but I have something to go off of now. So I check it again with my analog angle finder (used the level app on my phone the first time) and low and behold... I am way off.
Well crud, now what? I look into pinion shims, quick cheap and easy. No dice because I have the extra long "anti-wrap" Ruffstuff spring perches that are 8" long, the longest shim I could find was 5". Then I was scrolling on here and noticed a guy with a second gen, it looked like his transmission crossmember was lower and they used a thicker trans mount to make up the difference. Now we are on to something. Except that there is no downward adjustment left with my crossmember.
So I dig the crossmember out of my dad's grainery and flip my pickup box trailer in process up on its butt and measure.
Gonna call that 1-1/2" above the bottom of the frame.
So then I crawls under my truck, the perspective makes the top look weird but I did my best to line it up. 2-1/2", a full inch different!
Ok, lets call that a plan B. The brackets on my trailer are very rotten and riveted on the frame to complicate pulling another set from a yard. The second gen mentioned earlier bolts on, easier to pull and easier to mount. So I hit the JY.
The least crusty one there was in a '93 Explorer. I did measuring back and forth and the frame doesn't get wider until RIGHT after the trans crossmember. I also measured it to be 1-3/4" above the frame. So I give up a quarter inch of adjustment to get a much easier to work with crossmember.
Still nervous about the frame thing I compared to a 2wd third gen, same same. Also eyeballing it for fitment it looked to be about a quarter inch higher.
Back to the ranch I head with my treasures:
Before I start I measure just for giggles:
Look ma, no crossmember!
And it bolts in! I think the holes are there for dogbone style crossmember and this one uses two on the passenger side, kinda neat.
Or almost bolts in... had to break out the die grinder.
And it is down 3/4" on the nose.
Crossmember is holding the transmission:
Angle still is not ideal. Pinion is up 1.5* compared to the transmission. I suppose without the Belltechs it would be right on. Given I have dropped the trans a ton I am going to give it a go and see how it is. I need to work on the t-case mount yet but otherwise I am optimistic so far.