I have to put jack under front of engine to tilt it back to install dog bone. A 3.4 auto with all mounts replaced. Sitting without dog bone the distance is 4 5/8". Dog bone is 4" c/c. Sh
ould dog bone be under tension at rest or should I buy adjustable/custom dog bone?

Dog Bone and other mounts Should Not be loaded w/ parked on level ground and trans is in neutral.
All must take proper loads in both forward and reverse gears.

Trans not in neutral or parked on uneven ground can load mounts just leaning on car or weight of engine etc enough to fake problems in the drivetrain and mounts.

Have problem w/ DB can have problems w/ other mounts too pulling the engine front/back. Don't think X size DB until you check all mounts.

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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

See what others say (Ogre's post appeared while I was posting), but IMO 5/8" difference isn't much to worry about.

Can you not get the bolt to go through by rocking the car back and forth with the auto tranny in Park and the parking brake released?

[This message has been edited by Patrick (edited 04-06-2020).]

I just measured my 85 SE V6 dogbone- Both Center-to-center (3 3/4") and overall length (6").....



Here is a pic of mine; I have Poly in one side....and my engine had to be tilted a little to make it fit- so I installed a 1/8" washer to get to neutral point......

I installed spacer. The Dog Bone bolt slid right in. I had difficulty in threading bolt thru spacer therefore installed bolt first and inserted spacer cut to "U" configuration. Rubber bushing OK, otherwise I would have bought a suitable dog bone; West Coast Fiero custom length $65, Rodney Dickman Fiero, adjustable solid/no bushing $65. (Dickman has an adjustable Dog Bone with poly bushing but max length is 4 1/8")

I checked mounts and cannot see a problem.