Torque converter bolts loosening. Advice?

[redfuelrules]

Hi everyone.



For the second time now, a torque converter bolt has loosened, made contact with the engine/transmission adapter, and sheared off.



Page 21-1038 in the 05 factory service manual says to torque coverter bolts to 35 ft. lbs.



First time I installed the (suncoast) converter, I used blue loctite and tightened to 35 ft/lbs. I pulled the inspection plate on the bottom of the bell housing about a week later after a grinding noise developed, and a converter bolt head fell out. I pulled the transmission, took the converter to a machine shop and had them remove the broken bolt. The threads in the converter looked fine. I reinstalled converter, torqued all converter bolts to 42 ft/lbs upon reinstallation. Again used blue loctite.



Now a month or 2 later, another converter bolt loosened and sheared... Has anyone torqued these bolts higher than 40 without negative results? I am still reusing the remaining converter bolts from my original transmission. Should I try red loctite? Just wondering.



Asking for advice so I don't cause this to happen again. I love this transmission, but I'm sick of pulling it from under the truck...



Thanks

Ben

 

[CBrahs]

I would buy new bolts and use red loctite. torque to factory specs that way you don't over-stretch the bolts and cause other problems.

 

[Lightman]

Make sure the holes in the flex plate are not oval or over sized I had this problem and had to put in a billet flex plate to solve the problem.

 

[WVanHemert]

For that size of bolt I would defintely use red Loctite, for the amount of vibration and rattling going on in there.

 

[rbattelle]

Just another suggestion - you could use distorted-thread locknuts. That's what my old Bronco II used and they work perfectly without the need for Loctite. The catch is, you can't reuse them - they have to be replaced if removed.



Ryan

 

[redfuelrules]

Thanks

Thanks everyone.

I think I'll try new bolts and red loctite.



Ben

 

[Allnew2Me]

I just installed a Suncoast converter and they were very specific regarding the bolts. They said to use only those bolts that were supplied with the converter. I think the length of the bolt is the issue here so the case doesn't warp with too long a bolt. I would suggest that you get the proper bolts from Suncoast to insure that they are not the problem. I torqued mine to 35 ft. lbs. and used blue loctite also and so far all is well. The only other thing I can think of is to check that the TC itself is all the way forward and seated in the crankshaft properly so the bolts are bearing on the flexplate properly.