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NV3550 Advanced Adapters Cross Member on a 1971

rockingm82

Sr. Member
Joined
Apr 11, 2006
Messages
486
Loc.
St. Peters, MO
I have a 302 mated to an NV3550 with the Advanced Adapters' kit. With everything connected, the engine would not sit level. Determined the cross member was preventing the engine for seating into its mounts correctly. Looking at the cross member, the pre-cut slots appeared to be 1" off. After much head scratching, web searching, engine wrastling, I called Advanced and they informed me that specific to the 1971 Bronco, the pre-cut slots are 1 inch off. I cut new slots and enlarged the hole on the bottom of the cross member for socket access and now it sits level. Hopefully, this doesn't create further difficulties.

I just wanted to post this as a public service announcement. Advanced Adapters is very helpful on the phone.
 

ChrisC74

Sr. Member
Joined
Dec 9, 2010
Messages
901
How old is your kit / cross member? It is too bad they have not fixed this issue yet or at least alerted you in the instruction manual. They have problems with the 74 broncos also. At the time of my install they acknowledged it was a known issue but never did anything that I know of to fix it...
 

73azbronco

Contributor
Bronco Guru
Joined
Nov 11, 2007
Messages
7,796
I had the nv4500 adapter and mount for a 73, same issue but i did not have to cut new holes, i did have to "massage" the motor level by loosening all mount bolts on engine and tranny crossmember, and using a 6 foot pry bar to "help" it into place, than tightened everything up level.
 

AZ73

Contributor
Bronco Guru
Joined
Mar 28, 2012
Messages
3,541
My 73 has a level engine, but has the problem where the engine sits crooked (centerline runs from the front left to the back right) because of the trans mounting slots. Was told this is a 73 problem %). I guess every problem they have in their manufacturing is a problem with whatever year your Bronco is.
 

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rockingm82

rockingm82

Sr. Member
Joined
Apr 11, 2006
Messages
486
Loc.
St. Peters, MO
How old is your kit / cross member? It is too bad they have not fixed this issue yet or at least alerted you in the instruction manual. They have problems with the 74 broncos also. At the time of my install they acknowledged it was a known issue but never did anything that I know of to fix it...

My cross member is an older model no longer offered on their site, but the new model bolt slot placement doesn't look any different. At least they knew it was a known issue when I called. I didn't want to cut and drill until I was absolutely sure. They removed all doubt.
 

jmangi62

Bronco Guru
Joined
Jul 28, 2013
Messages
2,469
I must've just been lucky, I have the AA kit on my 70 and I didn't have to modify anything. Initially I thought I might have to clearance the xmember for the front driveshaft to clear, but didn't even have to do that, just got lucky I guess. My kit is approx. 4yrs old. ;D
 

MarsChariot

Contributor
Planetary Offroader
Joined
Oct 12, 2004
Messages
2,469
Loc.
Albuquerque, New Mexico
Same here. Original AA 3550 kit from a decade and half ago on a 71 and, while there were some tight holes on the cross member, it fit o.k., or at least it was doable. Must be variations in tolerances.
 

JB Fab

Sponsor/Vendor
Bronco Guru
Joined
Mar 21, 2004
Messages
1,240
I can tell you when I put the Advance Adapter AX-15 kit in the wife's 67, I was prepared for the worst..... It went in perfectly, Advance Adapter NAILED that cross member, everything lined up on a 50yr old frame that has seen some serious abuse
 
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rockingm82

rockingm82

Sr. Member
Joined
Apr 11, 2006
Messages
486
Loc.
St. Peters, MO
I can tell you when I put the Advance Adapter AX-15 kit in the wife's 67, I was prepared for the worst..... It went in perfectly, Advance Adapter NAILED that cross member, everything lined up on a 50yr old frame that has seen some serious abuse

Never thought about the frame being out of whack. Good point. Steve (AWS) is rebuilding my D20 with your kit. Once I get that back we'll see how everything lines up.
 

Mitche11

Newbie
Joined
Jul 14, 2012
Messages
29
NV3550 Advanced Adapters too tight, front driveshaft doesn't fit

I'm just finishing getting my 72 rebuilt and I'm having the same problem. The engine slopes down in the back, and the front driveshaft rubs on the bottom of the cross member and interferes with a tab that is close to the heim joint. I called Advanced and they told me to clock my transfer case up to the next bolt holes. Looking at what that would do to my linkage, I'm not thinking that the existing hardware will fit at all. On Sat I went to a Bronco breakfast and crawled under every bronco running the stock transfer case and cross member, and confirmed that mine is clocked in the stock position; where they say it should be in the instructions. I think I'm going to try to space up the back of the tranny off of the cross member and hope that gets me the needed clearance. If I have to drill holes to get it up, I guess I will, but what a PITA! Ugh.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
47,345
Wow, good luck Mitch. And welcome to classic too by the way!

The engine does sit low in the rear though, right from the factory. Without much room to go farther in fact, before the rear of the cylinder head hits the firewall on the driver's side.
What angle is yours sitting at now? See if you can get a couple of readings and some of us can compare to see what's going on.

And if you go the shim route, keep an eye on your fan shroud (if it's installed) so you don't put the fan into it.
If it is installed and you're doing this on your own, might want to disconnect the shroud and let it sit on the fan so it's not in the way while things are moving around.
Not that there is not some wiggle room of course. Just that while you're jacking around in the back of the drivetrain you don't want the front going where it's not wanted.

But others have had the driveshaft issue as well, so maybe they've had luck with getting it to clear too.

Good luck.

Paul
 

bronkenn

Contributor
Bronco Guy
Joined
Apr 27, 2017
Messages
2,662
Loc.
Southeast Ohio
I just did my 72 with the M5OD and had the same problem. I reclocked my transfer case up one step and everything fit well. I have JBFab twin stick and had to do a little bending on the shifter arms to clear everything. It shifts good now. Now need to bend shift arms to try and get them to come out the original hole in the floor pan. Ken
 

bronkenn

Contributor
Bronco Guy
Joined
Apr 27, 2017
Messages
2,662
Loc.
Southeast Ohio
I have the Duff's ceramic headers on mine with the crossmember from AA for the M5OD. The headers don't fit it particularly well. The right side is good but the drivers side is going to take some fudging on the pipes to fit right. A friend has a bender so I will be bending my own to make it work. Hind sight I would have gone with shorty headers as I want a 2 in 1 system. Ken
 
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