4.0L rod bolts - reuse or new?

[Mtn_Man]

I'm rebuilding my wifes 4.0. This is my first 4.0, but not my first engine. The rod bolts are torque to yield, so I'm thinking I need to replace them, but the shop says otherwise. the only source seems to be Ford, and I'm not liking the idea of paying the usual ransom. What do you guys do?

 

[dogfriend]

I would think about the risk to benefit ratio. The risk of failure is much higher (IMO) than the cost of new bolts. I would search online to see if I could get a good price, but I would replace the bolts (JMO).

 

[aldive]

Use new ones.

Goos luck ....

 

[Creager]

the rod bolts (and the main bolts) are not torque to yeild, and can be reused. Although drilling the holes out and replacing them with new ones would be a good idea.

the harmonic balancer bolt and the head bolts are torque to yeild. I've read from a few different places of people reusing all these bolts on their 4.0 rebuild without a problem (instead of the head bolts, never reuse headbolts).

 

[Mtn_Man]

Maybe I'm confusing them with what came later. I have the 97 Explorer/Mountaineer shop manuals (because of my 97 Mountaineer) and was following the bouncing ball in it while rebuilding the 4.0. It does state that the bolts are TTY and gives the settings as 20NM + 90deg. So the earlier models are not TTY?
BTW: the 4.0 I'm rebuilding is a 94.

 

[Mtn_Man]

Just got off the phone with the dealer. Their shop foreman tells me that 94's are not TTY, 23-29 ft-lbs so it looks like it's good to go. With a torque that low, I'm not going to sweat using the originals.
Thanks guys!

 

[Creager]

good luck man, if you have any questions, i finished rebuilding my 4.0 less then a week ago. All this info is fresh on my mind

Im glad you found out from a dealer what the torque specs were for those rod bolts. I had one hell of a time trying to find that information, and when i did i got a simple '24ftlbs,' from the autozone webpage... ugh ya... autozone... i didnt know who to trust, but i went with it, and now im happy.

Edit: Make sure you torque those rods in 3 equal steps. 8, 16, 24 is what i used. I also stuck a .003" feeler gauge between the cap and the crank to keep the cap from twisting and disturbing the position of the bearing.

 

[ironbandit]

I'd have to say that the note about TTY on the con rod bolts is erroneous. At least for the Gen 1 4.0L OHV mills. Haynes and Chiltons both give a torque value in single numbers, not like the head bolts with 2 plus the additional 89 degrees.

Also, Ford has discontinued these bolts, so finding them may be extremely difficult.

 

[jd4242]

I'd have to say that the note about TTY on the con rod bolts is erroneous. At least for the Gen 1 4.0L OHV mills. Haynes and Chiltons both give a torque value in single numbers, not like the head bolts with 2 plus the additional 89 degrees.

Also, Ford has discontinued these bolts, so finding them may be extremely difficult.

You know this thread is over 7 years old.....just a fyi you can use 302 bolts

 

[malohnes]

It's cool to dig this info up once in a while...some of us haven't searched all the wealth of knowledge this forum contains!

 

[jd4242]

It's cool to dig this info up once in a while...some of us haven't searched all the wealth of knowledge this forum contains!

absolutely..