Dimensions for converting rear from leaf to coil

[steinepstein]

I'm converting my 68 GMC from leaf to a trailing arm setup....

Does anyone have trailing arm perch dimensions? Those perches are welded on at an angle and are set at some distance from center. I'd love to get those dimensions, any help would be appreciated.

I realize that I could take the truck to a chassis shop and they could line everything up straight and square and weld it all up, but I'm not at that point yet and don't really want to haul it all over there either.

If I am going about this wrong, please let me know, thank you.

[aggie91]

I have requestd this info too in the past. SCOTI is working on getting me this. If he does, he may post it here too or I will pass it along. He has a chassis sitting on a table while he is setting it up.

Another way, is to put in the crossmember, install the trailing arms in a position that keeps them from binding in the front mount. Set the saddles on the arms, set the rear end on them and set the pinion angle, then weld them up. I sort of did this when I put my 9" under mine. I just happened to start with a truck that was coil to begin with.

Hopefully, I will get the measurements soon.

[fixit-p]

If your refering to the brackets which bolt to the TA cross member I have it on a disc I check tomorow as far as the cross member it should already be there IIRC my 65 GMC with leafs has it and it's already drilled for the brackets

[Wild83C10]

Originally Posted by aggie91

Another way, is to put in the crossmember, install the trailing arms in a position that keeps them from binding in the front mount. Set the saddles on the arms, set the rear end on them and set the pinion angle, then weld them up. I sort of did this when I put my 9" under mine. I just happened to start with a truck that was coil to begin with.

That is the way CPP did it on their 79 conversion and that is how I am doing mine. Having the dimension as a reference isn't a bad idea but it doesn't mean yours will sit at those exact dimensions.

[steinepstein]

thanks guys!

[fixit-p]

Not sure if this is what your looking for, but here it is. My 69 3/4 ton with leafs also already has the TA x-member. I also have a pdf if this isn't readable

[steinepstein]

fixit,

thank you, this is also a valuable drawing, but more specifically, I'm looking for the perch dimensions from the rearend - distance from perch to perch and angle of perches

thanks,

JE

[fixit-p]

Ahh, I'm at the wrong end, I too need that info so I'll stay tuned and if I find anything out I'll be sure to share.

[aggie91]

SCOTI got this information for me. He measured the center to center of the rear hole of the axle pad to be 41.5" and the center to center of the front hole in the pad to be 39.5".

I will be doing a layout of this in autocad and could send out a PDF if someone needs it. I will get the rest of the info I need tonight to do the layout.

[SCOTI]

Originally Posted by aggie91

SCOTI got this information for me. He measured the center to center of the rear hole of the axle pad to be 41.5" and the center to center of the front hole in the pad to be 39.5".

I will be doing a layout of this in autocad and could send out a PDF if someone needs it. I will get the rest of the info I need tonight to do the layout.

Get @ least one more confirmation on the dimensions first (I could be cross-eyed ).

[steinepstein]

Greatly appreciated. Please let me know if you ever need a favor, happy to help.

[fixit-p]

Originally Posted by aggie91

SCOTI got this information for me. He measured the center to center of the rear hole of the axle pad to be 41.5" and the center to center of the front hole in the pad to be 39.5".

I will be doing a layout of this in autocad and could send out a PDF if someone needs it. I will get the rest of the info I need tonight to do the layout.

If you don't mind I would like a copy.

[m6z]

Does anyone know if the leaf spring trucks have the holes predrilled for the trailering arm crossmember?

[SCOTI]

Originally Posted by m6z

Does anyone know if the leaf spring trucks have the holes predrilled for the trailering arm crossmember?

67-72 leaf equipped trucks should already have the TA c.member installed (w/o the TA brackets). That c.member was also used for mounting the carrier bearing.