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TR6 TR6 Trunnion/Lower A-Arm Bolt--Torque or End Float

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kurts100

kurts100

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Bought my first TR6 last March and just finshed up totally redoing the front suspension. The only item I'm not sure of is the main bolt that goes through the lower A-arm ends (outer) and the trunnion for the vertical link. It has the 4 Nylon bushes, thin rubber washers, cupped washers, thick washers and distance pieces.

One book says to torque to 50 to 60 ft. pounds (which doesn't make sense to me, thinking that you'd crush the nylon bushes and not allow much movement there) and the other book says to snug tight and then back off nut 1 or 2 flats to end up with a bit of end float (think it was around .004"). This makes more sense to be but figured I better ask the experts.

Thanks for any help on this!

Kurt
 
When I (re-)did this on my 4A, this was something I could never really get a clear answer on (the 4A has a similar setup to the 6). Originally I followed the instructions that have you set the end float, but I think this isn't correct for the 4A (and 6) trunnions. When I re-did it, I used the TR6 torque values, and believe that is the correct procedure. The nylon bushes are somewhat self-lubricating, and appeared to not impede movement of the suspension even at that torque value. Having them looser was wearing the hole in the trunnion where the bolt passes.
 
Thanks Darrell for the info. I'll try torquing them down and see how that works. Surprised the different manuals have conflicting information. Pretty sure it's a Haynes Manual that wants end float, where as the factory manual from British Leyland says to torque to 60 ft. pounds. Also noticed different torque settings for wheel studs (60 vs 80 ft. lbs.). Guess either one will hold a wheel on.

Anyone else have any info. on which is the correct method?

Thanks!

Kurt
 
I can't explain why the different TR6 manuals conflict. In the case of the 4A, even the factory manual was just some additions where the 4A differed from the 4. But there wasn't any part that talked about the trunnions, and the 4A has trunnions like the 6, and the 4 has ones like the 2 & 3.
 
on a side note, snug things up, and then tighten them with the car on the ground and full weight on the front, I think you will have better results and less binding of the suspension, wish I would have done it

Hondo
 
I even found a factory TR250-TR6 manual that calls for end float (and also has TR2-4 style trunnions pictured).

However, I am fairly certain that the TR4A-TR6 style trunnion should have the bolt torqued down. It should come up against the metal sleeves and keep them from turning (just like on the lower inner pivots) and whatever clearance is required is presumably built into the sleeves & bushings.
 
Thanks for everyone's input. Torquing it down tonight. Guess that makes sense that the 2 sleeves act as distance pieces and only allow it to go so far when tightening. It's kind of an odd set up with those skinny little nylon bushes. I smeared grease on them and everything else in that set up even though it doesn't mention any kind of lubrication. Looking forward to getting it aligned and finally getting it on the road after 7 months on the jack stands. Did alot of other things to it besides redoing front end. The guy I bought it from painted it Brockway Yellow Chrome (School Bus Yellow), so it will be easy to spot me. Originally Laurel Green, which is one of the reason's I bought it. Someday will paint it back to original color.

Thanks again!

Kurt
 
Well, I finally torqued the main bolt that goes thru the trunnion and lower A arms to 60 ft. lbs. and found that it seemed to bind that pivot point. Had a friend push up and down on the fender while I watched what was happening at the trunnion and it didn't pivot at all. I figured that can't be right so I decided to back off nut, but instead of having .004" to .012" of end float like the Haynes manual calls for, I took them to hand tight with no end float and then snugged them approx. 1 more flat on the nut until my hole lined up with the castellated nut. This way the trunnion and A-arms pivot but there's no slop.

Guess I'm learning not to always believe some of these manuals. Also, set front wheel bearings the way the manual said with about .004" of end float and when I put the wheel/tire on and rocked it back and forth at top and bottom there was too much slop in it. Tightened it 1 flat from where it was and it was much better.

Kurt
 
Sounds like you were drinking the wrong kind of beer. Should have had Dogfish Head!
 
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