Need advice on achieving PTO/body clearance

[steves]

I am installing a Spicer single-stick PTO in my CJ3A.  I lack about 0.5 inch of clearance between the PTO and the body.  I can achieve the necessary clearance by lowering the transmission crossmember.  Does anyone have advice about the advisability of doing this?  Are there alternatives?  My PTO instructions mention a spacer kit, but I haven't found anything online.

[oldtime]

Is this a standard Spicer 18H PTO that is being attached direct to the transfer case.
Is this an other wise standard cj3a ?
If not what relative parts were modified ?
Such as overdrive with warn  adapter etc.....

[steves]

Is this a standard Spicer 18H PTO that is being attached direct to the transfer case.
Is this an other wise standard cj3a ?
If not what relative parts were modified ?
Such as overdrive with warn  adapter etc.....

It's a standard Spicer 18H PTO.  I am attaching it to a Saturn OD.  The CJ3A is low mileage and stock, although the previous owner (>11 yrs ago) took the body off to paint it.  Body/frame spacers appear to be 0.25 inch rubber and are in good shape.  The transmission cross member was bolted tightly to the frame with no spacer, and I was able to install the PTO by loosening the four bolts about 0.5 inch.  I have ground about 0.125 off the flange on the PTO and its adaptor, but I still need about 0.375 inch.

[oldtime]

An 18H bolted direct to the transfer case will not need an adapter.
In this instance the 18H has been moved rearward 6-3/4”because of the overdrive and the overdrive adapter.
The body tunnel gently slopes downward in this area.
The tub will only need to clearance the 18 H in the area of the shift lever and that is normal.

If your body tub (original tub) has a PTO shift lever port then you will want to reposition it rearward.
Do not simply move the hole rearward by 6-3/4” of misalignment may occur.
Mark the tub area where the PTO actually needs the port.
If your body tub is aftermarket you will need to add the port hole for the PTO to enter.
The standard port hold is about 2-1/2” square with 1-1/4” radius at the corners

[steves]

I've cut the shifter hole and installed the PTO, but one bolt flange on the PTO (upper bolt, driver's side) and the top of the circular flange on the adaptor are going to press against the underside of the tunnel if I tighten the bolts on the crossmember.  I actually cut the hole for the shifter 0.5 inch forward of the shifter boss on the PTO so that the uppermost part of the adaptor flange has clearance and slightly extends through the shifter hole.  The printed instructions that Herm Tilford sent with the OD/PTO adaptor mention a spacer kit, but I haven't found anything on line. 

What do you think will be the consequences of permanently lowering the crossmember by about 0.3-0.4 inch using a spacer?  I can fabricate something easily.

[oldtime]

Well I just recently fitted a spiced 18H behind my Warn overdrive.
But my PTO came back even further than yours because I had to move my crossmember an additional 5-1/2” to the rear in order to run a T98 transmission.
In my instance the tunnel area was re-made a little wider and higher to fit the extreme rearward positioning of the PTO.
I still have my crossmember bolted direct to the frame.
But yes technically it should be absolutely fine to lower the crossmember via spaced blocks.
In fact that’s exactly what Jeep did when they installed a T98 into a CJ-5.
Factory CJ-5 with T98 used two 1” thick oak wood blocks to lower the drivetrain for tub clearance.

So yes if your content with lowered crossmember that should be acceptable.

By the way on another CJ3B I did two years ago where I fitted a Koenig PTO behind an overdrive.
I had no clearance issues with that install and a factory 3B has the same floor pans as a 3A.
So I am estimating you have an aftermarket body tub ?

[steves]

I believe I have an original tub, but the body spacers may have compressed a bit. 

I put in the PTO and tightened up the crossmember bolts.  Everything works, but the PTO and PTO/OD adapter are pressed tightly against the tunnel and I can hear a bit of tranny whine that I couldn't hear before.  The tub is picking up the sound from the tranny and amplifying it.  I think I am going to try to raise the tub a bit with some thicker spacers. 

The PTO works like a champ and is smooth as silk.  At idle, I can shift it in and out without using the clutch if I am careful (which is probably not an advisable long-term practice).  I pumped about a pint of gear oil in through the shifter hole before final assembly.

[oldtime]

Yeah that all makes sense.
Regardless its going to be a very close fit with the pto moved back.
The side of the tunnel slope gets close.
I like to pull out the pto lever so I can fill the transfer case from there.
IMHO it’s certainly worth it in the end to have both OD and PTO.

[steves]

Thanks for all the good advice Oldtime. 

I have temporarily put 0.5" steel spacers between the crossmember and frame.  I think that eventually I'll put in thicker body spacers when I can find some suitable rubber. I don't like the idea of losing even 0.5" of ground clearance.  I'm getting the drive shaft cut down and balanced, and it looks like I'll need some minor exhaust pipe mods to fit it in.  I'm going to use the PTO for a small drawbar-mounted irrigation pump so that my hobby Jeep can start to pay for itself.