Torque on ball joints

[Ron Earp]

How much should one torque the uprights to the ball joints? The ball joints on my RF are good size, using a 22mm nut if I'm not mistaken on a beefy shaft. Any suggestions?

Ron

Ron

I regret I don't know a torque figure but these ball joints are ones you don't want coming loose.

I recently have dismantled all the front suspension and upon examination found the holes for the ball joints were ever so slightly oval. I had a chat with Ray Christopher about it and said he had a similar problem recently too.

He felt the problem was caused by loose ball joints. I do mine up good and tight, however Ray felt that if your uprights are powder coated, or similar, then the tightening up of the nut causes the coating inside the taper to break up and move a fraction. Of course it feels good and tight and you can get good torque on it. But when in use that fraction of broken up powder coating or whatever moves again under load and hence the ball joint is no longer properly located or tight. The hole goes slightly oval.

His soluition is to file off any coating prior to fitting and to ensure you get a good fit.

I have no idea how true this is but the powder coating on my old uprights was breaking up inside the taper.

I am making some new tapers for my new uprights anyway but thought this might be of interest to you.

Malcolm

[Clayton]

Ron

The uprights look very similar to TE Cortina ones. The factory manual indicates at torque of 80-102 Nm on both upper and lower ball joints.
regards

Clayton

"How much should one torque the uprights to the ball joints? The ball joints on my RF are good size, using a 22mm nut?"

at work it would be a 1/2 impact gun or an extra long snap-on wrench. REALLY TIGHT

22mm/7/8" is a 5/8" thread dia.? if I had to guess a torque I would say 80 to 100 ft/lbs.

torque can generally be calculated by thread diameter and material(not nut size)

red locktight is always nice on brake and suspension stuff that doesn't have a cotter pin you can even take up some of the "oval" damage with it.

torque calculator http://www.futek.com/boltcalc.asp

for a 5/8 bolt I get 125 lbs.

[ May 23, 2002: Message edited by: Kalun D ]

[JayT]

Kalun, nice site, very helpfull, Thanks

[Peter D]

Not sure if this helps, but the DRB uses '87 Corvette front suspension, & the recommended torque setting are :

- Upper Ball Joint =37 ft lbs
- Lower Ball Joint = 50 ft lbs
- Upper Arms/Chassis = 37 ft lbs
- Lower Arms/Chassis = 82 ft lbs

Kind Regards,

Peter D. [img]images/icons/smile.gif[/img]

[Peter D]

I forgot to mention - the 'Vette ball joints now come with some type of dark grey "sintered coating" on the tapers. Apparently, they had a lot of trouble with bare steel on the tapers mating with the alloy of the arms - corrosion, freezing, etc. The advice is to not coat anything in the taper at all.

Kind Regards,

Peter D. [img]images/icons/smile.gif[/img]

[patbarry]

Seems like this has worked its way through, but a couple of other comments...Coatings typically impact the degree to which a bolted surface can withstand movement - it's called a faying surface. A coating like an epoxy (which is basically what a powder coating is) will allow a slip critical connection to move more than it should. This slipping is probably what people are seeing as fracturing the coating. My advise would be to remove all coating prior to bolting the connection.

If you do want to coat the bolt, either do it after the connection is made, or use a coating that is meets the requirements for a slip-critical connection (there are ASTM tests for these types of things).

Hope this helps.

Pat

[Mike Coates]

I have just installed Ford ball joints on the front of my GT40 and the leaflet that was in the box indicated the following re torque. (9/16 stud size)

Quote... Install nut and torque to minimum specification of 60 ft lbs. When the minimum torque has been reached, locate cotter pin hole in stud and then continue to tighten nut until slot in castellated nut lines up with hole (max torque is 90 ft lbs) Do not back off nut when locating the hole.
Unquote..
As other have indicat above I would recommend that any coating is removed from the tapered hole in the knuckle as a coating could effect the torque.The torque may not be maintained.

[MK -IV J6]

Hi
Instead of cassleated nuts and cotterpins one can use stamped jet nuts which can be locked in place without having to over tighten.

[Navid M]

I just saw that the link posted up top was broken: here it is...

Bolt Torque Calculator: FUTEK Bolt Torque Calculator | Bolt Torque Calculators

[Bill D]

Navid
This post is almost 6 years old. Ron no longer has his RF GT40

[Navid M]

doh!~