Help mounting 4spd shifter

[Michael L.]

Guys,

I'm trying to mount the shifter to the mounting plate and having some trouble. My assy guide shows only two bolts with no nuts, but one of the mounting holes (the top)has no threads. Also, when I place the shifter on the plate it sits crooked, like something such as a spacer is missing. I attached a couple of pics to show what I'm describing. Any assistance is appreciated.

Mike

[Stephen L.]

Re: Help mounting 4spd shifter

I've studied your photos some and I believe you are missing a weldment (Threaded) at the top hole, which would also act as a spacer. Did you disassemble this yourself or did someone else? I don't have a photo of the bracket itself nor a photo without the shifter mounted so I can't verify for sure. Your photo appears to have the remnants of a spot weld in the area of the non-threaded hole. You are correct about there should be no nuts holding the shifter to the bracket.

[Michael L.]

Re: Help mounting 4spd shifter

Thanks Stephen. The only problem is if I were to place the spot welded nut on the side the shifter goes on it would only exacerbate the degree of tilt the shifter has. Also, the area where the spot welds are seen on the bracket is on the pass side. Here are a couple of photos of the shifter installed. Maybe someone can comment on the alignment of the shifter.

[Stephen L.]

Re: Help mounting 4spd shifter

Did you remove this bracket or was this a "basket case" car. In the photos you just sent the bracket appears to be slanted toward the diver side. I believe it should be vertical. Could it be bent? Could the frame mount be bent? Could the shift mechanism be assembled incorrectly?

[Joe L.]

Re: Help mounting 4spd shifter

Michael------


There needs to be a weld nut at BOTH the upper and lower positions. Your bracket has the top weld nut missing. There's a reason for this. The long thru bolt threads into the top nut. This bolt and nut endure the stresses imposed by rambunctious speed and power shifting. Apparently, yours gave way. The long bolt sometimes cracks or breaks. The long bolt was GM #3733134 and is the same as the small block long exhaust manifold bolts. ALWAYS use NEW bolts when mounting the shifter linkage. DO NOT use used bolts.

Is your bracket currently attached to the frame crossmember via the 2 bolts on the rear? If so, I'd say this bracket must be bent.

By the way, there were 3 iterations of this support bracket. The first was GM #3921629. It was used for 1968-E71. This is the one you have. The second was GM #3992325 and was used for L71-72. I've never been able to discern any difference between the 3921629 and the 3992325 although there must be one. The third was GM #334943 and was used for 1973-81 and also became SERVICE for earlier C3. This is the best bracket. It has a thick, welded-on, steel reinforcement which spans the 2 holes and has tappings for the bolts on either end. I believe GM came up with this to remedy problems with the earlier brackets, most probably involving the aforementioned problem.

[Michael L.]

Re: Help mounting 4spd shifter

Thanks Joe. I cannot discern any damage to the bracket but I ordered an new one (original OEM) from a vendor. I will see if it is any different when it comes.