TR4/4A Front Suspension Re-assembly

[mcmillal]

So I am about to re-assemble my front suspension and had a question about the vertical link and trunnion. I have brand new trunnions and grease nipples. Do I grease the threads on the vertical link before I screw them into the trunnion, or can I simply apply the grease afterwards through the grease nipple on the trunnion? Also, does the steering stop needs to be set a particular way. I believe the hole is not in the center. How should it be aligned?

.......Thanks, Alex

 

[CJD]

Hey Alex,

I would do both...grease the trunnions well before assembly, and again using the fitting once the entire suspension is together...along with all the other pivots and joints.

The stop is, indeed, off center. The intent is to set the maximum steering angle by turning the off-center washer to hit the stop at the appropriate angle. One side sets right turn limit, and the other sets the left limit.

 

[bobhustead]

The manual gives degree values for the front and rear stop positions. (only one can actually be set, of course) These are set using a machine that a front end shop has. It is a little turntable with arc marks. You may be able to see wear marks on the stop that you can use. In future, if you do the job one side at a time, you can reset the left front stop from bumping the steering to the right rear, etc.

Bob

 

[KVH]

Can you just skip the stops? Leave out the bolts?

 

[bobhustead]

No. The factory put them there for a reason. e.g., potentially dangerous oversteer. Bob

 

[Popeye]

FYI, there is polite debate on whether to use gear oil or grease in the trunnions. I'll let you search it, however as most (polite) debates, both sides of the argument hold value; it seems grease or oil will work. My DPO used some gray colored stuff in one of the two trunnions, and the threads had a shot-peened appearance - not good. The other one was greased and looked great. I'm using oil, FWIW, and filled the trunnion with it before assembly, and let it weep out as I assembled.

The adjustable steering stop is NLA, although it is a simple enough part that you could machine an offset part if you like. I am using the TR6 part, with no adjustment; I believe Triumph endorsed this as well.

 

[mcmillal]

I need to remove the old trunnions from the lower control arm assembly so I can install the new ones. Does anyone have any experience doing this? Is it possible to remove it by just removing one side of the lower control are assembly? Does is require some "gentle persuasion" or will it release quite easily?

............Thanks, Alex

 

[bobhustead]

The trunnion needs to be free of both control arms and the steering stop needs to be off, at which point the trunnion will easily thread off the vert link. If you have the stop in original position on one side, you can reset the opposite side stop by locking forward on the still assembled side and setting the back lock on the side you are assembling. Also compare the diameter of the splined section (where the lock washers fit) of the new trunnions to the old. My new ones were larger than the old and I had to drill the new lock washers to 31/64 to avoid stripping the nuts pressing the locks in to place. This allows a theoretical .007 interference fit and the standard for this diameter range is .003 to .016.
Bob