Stripped tie rod stud nut

jeep
compass

#1

2007 Jeep Compass FWD. The answer seems obvious in hindsight but I’ll ask it anyway. Changing the outer tie rod end last night. Existing end had a long stud that sticks up above the knuckle so that you can restrain the stud from turning with a socket while you crank down on the nut. Chrysler shop manual says to torque to 97 ft.lbs.

New Moog part has shorter stud with castellated nut and cotter pin. No instructions. I torqued the nut down to around 80 ft.lbs before the threads on the nut failed. At that point the nut had travelled so far down the stud that the cotter pin wouldn’t have engaged the bumps on the njt anyway.

Am I not supposed to torque this design as much as the factory manual says? Seems like you need to torque the taper on the stud tight anyway.


#2

I would stay with the carmaker’s spec., and get a new high quality castle nut and a high quality washer of the right thickness.


#3

Was it shown on the bag label? Google the moog part number and they have instructions available in pdf. Id expect the torque value to be half of where yours failed from my recollections 35-40 ft lbs


#4

It happens.

You get a defective part.

I was once tightening the nut for an outer tie rod end, and the tapered shaft snapped off before I reached the torque spec.

Tester


#5

This was a new tie rod end and a new nut, right? I always use a new nut on tie-rod ends whenever the old nut is removed, even if I’m using the same tie rod end. 97 ft lbs is the correct torque from what I can see. I haven’t done that job is a while myself (just a diy’er) but as I recall I hold the stud in place from below with a wrench, while I tighten the nut on top with a crow’s-foot wrench. I usually go to some trouble at the beginning of the process to get all the parts aligned correctly first, often using a couple bungee cords. There’s a jam nut on the tie rod itself that I leave loose until I’ve tightened the main stud nut, so the tie rod isn’t locked in any particular angle as it is pulled into place. then I tighten that jam nut afterwards. I seem to recall using a big c-clamp to get things lines up and held in place before tightening the main nut too. The parts involved are sort of springy and hard to get lined up otherwise. Some ideas for what might have caused your problem

  • stud wasn’t oriented perpendicular through the hole in the knuckle arm., but cocked at a slight angle.
  • nut was started cross threaded
  • wrong tie rod end, or wrong nut for the stud
  • defective part(s) right out of the box.

Suggest to take the original part to the auto parts store w/you next time, and insist the replacement part match as exactly as possible on all dimensions. I expect the part you purchased may be a compromise fit, so it will work in many different cars. Makes it simple to stock replacement parts, but the part doesn’t work quite right in some vehicles. .


#6

Worthy points raised, GSJ. One advantage to doing business locally is you can ask to look at the options they have in stock. I did the other day about brakes pads for my 2007 T&C van.

Also, if you have a problem with a part, you can take it back. They may very well offer a full refund and an alternative part. They did that for me about a water pump for another vehicle I had.

If they are really a pro-level shop and you need a new nut, they may just give you one.


#7

A new nut will do the same thing. It was already tight enough when the cotter pin would engage the nut. Normally only tightened until cotter pin hole visible. On these around 40 ft lbs. The taper is already seated, no need to keep cranking it further. The cotter pin keeps nut from backing off…


#8

No matter (97 or 80); both sound way too high for a thread that size.


#9

… which brings up the question: foot-pounds or inch-pounds?


#10

Thanks everybody. A lot of variance in opinions. :slight_smile: I can confirm that the shop manual states 97 ft.lbs, not in.lbs.

The original part was an online order, which I’m in the process of returning. The local parts store had a deal on an AC Delco part, which has the longer stud with the hex on the top, like the original. Installed it, and no problem so far. One parts guy thought that the Moog and Delco parts were both good quality, another one thought the Delcos were inferior. Good times.


#11

Cripes, a Jeep Wrangler is 35 ft-lb…this must be a mistake.


#12

FWIW, it’s not just a conversion error from metric. The book also says 135 N.m.

Come to think of it, I don’t think the stud is that much smaller than the wheel lug studs, and they take 100 lbs.ft.


#13

Yeah, but you proved it’s an error when you stripped it.

;-]


#14

Indeed. It’s not whether there’s an error or not, just the size of the error.

If the person writing the manual read the wrong table for this nut, I wonder what else they mistakenly put into the manual… Well, the wheels haven’t fallen off yet, so they can’t have screwed up too badly.

I’m still wondering if it was just a bad nut the first time 'round.


#15

Castle nuts are generally soft steel and torqued to 30-40 ft. lbs, I don’t believe a common castle nut will handle 97 ft. lbs. The OE nuts for those vehicles are much stronger.


#16

There was nothing wrong with the part. It’s not the same as the OEM part. It uses a cotter pin to retain the nut versus face/thread friction or a jam nut. If you’d take the time to go look at the Moog instructions online as I suggested in the first place, you’d see that.


#17

I’ve been arguing with my phone, and missed that. That clears it up. Thanks.


#18

Yeah, I’ve had same difficulties using my phone versus tablet or laptop. Biggest question is why the instruction sheet was missing. I’ve seen torque spec on the bag label too. Not easy to see unless looking carefully.