Hey all, I'm hoping someone can help me identify the correct parts I need to replace when swapping out the front lower control arm.

Looking at the shop manual, the small end of the control arm that bolts into the Rear Lower Control Arm, both the nut and bolt should be discarded. The next step shows that at the chassis (big) end of the Front Lower Control Arm notes that the nut should be discarded :




Looking at the parts catalog, I only see a bolt cam and nut (13, 14, 15) for the big/chassis end, and no parts for the small end.




Whats really weird is that I called Jag parts department, and they told me I need parts 13/14/15, but the shop manual says only to discard the nut from the big end, so part 15. And, the shop manual says to discard both the bolt and nut from the small end, and neither the catalog or the parts department had numbers for those parts. I don't even see them in the diagram.

So, what is it I need to replace, exactly?

Thanks!

 

Got a VIN? I can take a look at it in topix and EPC

 

Thanks, DMed you

 

Fortunately, this one has a completed RBoM (Repair Bill of Materials), with part #s for all the steps that need mandatory parts. Posted in the thread in case it can help others too.

The curved "forward" arm process shows the torques and steps, and as you said it only calls for replacing the bolt and nut at the other arm, it does not say to discard the bolt at the subframe end. The torque + angle is a indicator that it deforms when tightened and needs to be renewed each time. The subframe end just has a flat torque spec.

 

OK - Based on those materials here is what I've come up with:

 

OK I have a new wrinkle here. I searched up T4N3679/T4N3680 and which are called 'Ft Lower Control Arm Mount Bolt' and 'Ft Lower Control Arm Retainer Nut' respectively. Looking at the provided diagrams, the parts look like they are the correct ones. HOWEVER the inventory management system from the vendor is indicating this does not fit my vehicle. As someone who is a DIY mechanic, I'm not sure if this is sort of typical on these cars? It seems like this front suspension architecture is shared with other vehicles, so maybe it's just a known quirk in the parts catalog?



What's even more confusing is that if I follow the links that say 'However THIS part fits your vehicle, it gives me

1. The same bolt that is used on the subframe end of the control arm, and
2. a set of two nuts that belong to the upper control arm assembly, but is labelled 'Ft Lower Control Arm Nut'

It seems like maybe a lot of these nuts and bolts are interchangeable, same pitch/shank/length and so the parts catalog is kind of a mess.

I'm feeling like I should just go with what that Topix RBoM lists, but I'm better at turning the wrenches than I am at figuring this stuff out.

Any advice?

 

Topix is generally pretty damn accurate, outside sources like parts catalogs used by vendors can have missed updates and other things that would make them less accurate than the factory level. I'd assume if you order the part #s you have listed, you should get the right parts. Worst case you give them all a quick visual comparison before you take it apart to make sure.

Also, if you have to re-use the hardware, you won't have an issue. That happens more than it should, and it's always fine. I agree totally that we should be replacing the things that say to be replaced, but I can assure you that outside shops and independents are just jamming the same nut back on with an impact gun, and they never have issues due to a bolt breaking. The OEMs err on the side of caution way more than necessary in the real world.

 

Thanks a million Joe, I'll take that advice and I appreciate all the help!