Differences between '71 & '73 1210 PU's

[Scoutboy74]

Hi gang. The fat white boys are in the process of swapping a recently rebuilt 727 into a '71 1210 which originally had a bw 11 auto. This is a co-mingling of parts from the two 1210's listed in my signature. We have the 727 mated to the engine and resting on the dogbone crossmember. In a side by side comparison outside the vehicle the dogbones from both trucks appear identical. For lazy reasons (the dogbone from the '73 had far less accumulated guapo on it) we opted to use that one for the install as opposed to the one that came out of the '71. It took the use of a longer pilot bolt to get all the short crossmember bolts in place, but we got 'em all snugged up. The holes on the member are drilled to the exact bolt diameter, so there is no adjustablility front to back or side to side. The next step was to get the trans properly aligned so that we could secure the large bolt, spacer, and rubber mount assemblies. This is where we ran into issues. No matter what we've tried so far, it just doesn't look like these holes will ever line up with the transmission case. It appears that the engine/trans package needs to come back roughly half an inch (not realistic) or the dogbone needs to shift forward on the frame that amount. Is it possible that the member was mounted slightly more rearward on the trucks with bw auto as compared to the later ones with 727? I know we aren't pioneers here. I'm just wondering if anyone else has encountered a similar issue, and if so what steps were taken to correct it?
We're used to dealing with the much less cumbersome Scout II crossmember. Those are a breeze compared to the frikkin f/s dogbone. I hate 'em! thanks in advance.

 

[Michael Mayben]

hi gang. The fat white boys are in the process of swapping a recently rebuilt 727 into a '71 1210 which originally had a bw 11 auto. This is a co-mingling of parts from the two 1210's listed in my signature. We have the 727 mated to the engine and resting on the dogbone crossmember. In a side by side comparison outside the vehicle the dogbones from both trucks appear identical. For lazy reasons (the dogbone from the '73 had far less accumulated guapo on it) we opted to use that one for the install as opposed to the one that came out of the '71. It took the use of a longer pilot bolt to get all the short crossmember bolts in place, but we got 'em all snugged up. The holes on the member are drilled to the exact bolt diameter, so there is no adjustablility front to back or side to side. The next step was to get the trans properly aligned so that we could secure the large bolt, spacer, and rubber mount assemblies. This is where we ran into issues. No matter what we've tried so far, it just doesn't look like these holes will ever line up with the transmission case. It appears that the engine/trans package needs to come back roughly half an inch (not realistic) or the dogbone needs to shift forward on the frame that amount. Is it possible that the member was mounted slightly more rearward on the trucks with bw auto as compared to the later ones with 727? I know we aren't pioneers here. I'm just wondering if anyone else has encountered a similar issue, and if so what steps were taken to correct it?
We're used to dealing with the much less cumbersome Scout II crossmember. Those are a breeze compared to the frikkin f/s dogbone. I hate 'em! thanks in advance.

I have a "c" truck (2x4 manual trans) here and the two "d" trucks (727/4x4). The c and d frames are virtually identical.

The dog bone cross member on the c is further forward than the same on the d units. Multiple holes are punched in that diagonal brace on either side that ties the front crossmember to the frame rails, so obviously there were different "length" dog bone crossmembers used to mount to the diagonals. That in turn moves the engine fore and aft and determines fan-to-radiator clearance also (depending upon which radiator is fitted).

No doubt, there is a different dogbone crossmember position on the diagonals also between the borg warner trans rig and a manual trans rig, that would also be impacted by if it was a three speed manual or the four speed/five speed manual and just a 2x4 app.

Thinking this thru, I'd determine where the dogbone mount needs to go in order to make the fan-to-radiator clearance work, that locates the engine, then fabricate the rest of the package in the proper position.

You would have this same issue if one or both of the rigs had used the "horseshoe" front mount system. Iirc, the horseshoe front mount was used on the 1210/1310, the dogbones on the 1110 4x4. But I'm not positive until all the variations are researched by model version and 2x4 or 4x4 axles.

The '69>'71 "d" models have some significant differences as compared to the '72>'73. Then of course, the '74/'75 are different from the '73!

 

[Scoutboy74]

Mike, I think I May have cornfewzed the issue needlessly by improper terminology...akshoolee I'm blamin' it on jerry. Let's see if I can clear this up. Both trucks utilize the identical horseshoe front engine mount as the only engine mount. Engine/radiator orientation hasn't been changed and shouldn't need to be as we did not perform an engine swap. Same engine, different breed of automatics. I realize now I May not have been correct in referring to the transmission crossmember as a "dogbone", even though it does somewhat resemble one to my eyes. Perhaps the true dogbone is the other style of engine mount? Anyway, maybe the solution to this would be to remove the trans x-member that we installed from the '73 donor rig and re-install the one that is original to the project '71. Even though they appeared to be identical on a quick once-over eyeball inspection, maybe there are some subtle differences in the two which would solve the issue. Worth a try I guess. Other than that, all I can think of is to hog out the holes on one of the x-member to allow for some forward shift. Thanks Mike.

 

[Michael Mayben]

How tha hail wuud jerry know the difference inna horsehoe anna dogbone? Sumbitch thinks a horseshoe is sumthin' ya toss to a man (or a chick) overboard that May or May not have a line attached (depends if yore from somalia or not). And he thinks a dawgbone is sumthin' leftover froma deaddawg.

Hail man, cambo is the dam woodchuck in tha krew, kain't he jes' scab uppa chunka paralam or gluelam and hawgwire it in place for a crossmember? Maybe shoot in sum driwall screws for safetys?? Ya kidz is puttin' too much thinkin' in this pile!

Didyaawl 'member to stick a torque converter in tha hole too or iz jerry usin' it for a hemerude cushion?

 

[Scoutboy74]

Yep, jerry put wun uh them vishkus flooid kupling deevices wut he dun overhawled hizzownsef out of a fitty-two stoodibakur. Said it shud make fer a mightee nice performance upgrade. Thinkin's wut jerry duz best. Hez uhproachin this deel from all possible angulz. He'll either hatch a sulooshun 'er a cornback rattler purdy dam kwik.