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When/Where To Use Loctite

Redoing my entire front end, complete with upper and lower control arms, wheel hubs, brakes, shocks, pads, the whole nine yards! I am paranoid of nuts backing off over time as these are kinda critical to the safety of the car. My question…is Loctite necessary on these parts? I am concerned with the lower control arm where it bolts to frame, upper control arm in the same spot, and of course the spindle nut and the upper shock mount. Is it overkill to use Loctite, specifically red or blue, or am I just paranoid? Thanks for the advice!

No, you are not paranoid. Properly torque the fasteners to the manufacturer’s spec AND add a little blue Loctite to every fastener. The stuff will actually protect the threads from corrosion but will hold the fastener even if the self-locking nuts you re-used (I assume you didn’t buy all-new nuts and bolts) aren’t quite up to snuff. I’ve used this stuff on race cars that get pounded and disassembled time after time and it works. Don’t use red unless the blue just will not work.

And how can you tell if blue is not working?

If you are really paranoid about loosening bolts, make a paint mark across the bolt and nut and its mountings after tightening so you can check it at a glance to see if it turned.

Loctite isn’t normally used in the areas you describe. Properly torquing the fasteners will prevent them from coming lose.

Loctite is used in areas where the fastener is subjected to extreme vibration and where access to the fastener is difficult. For example, you would use it on the fasteners that hold the flex plate/flywheel to the crankshaft. Or on the fasteners that hold the pressure plate to the flywheel. Or on the fasteners that hold the torque converter to the flex plate.

If it didn’t come from the factory with a thread locking compound on the fasteners then it’s not needed.

And when you use Loctite you want to use the blue stuff. The blue Loctite allows removal of the fastener with a simple hand tool.

Tester

In anticipation of seeing a car again sometime in the future I have for years put gasket shellac on threads to prevent them from working loose or from seizing from rust. It’s a cheap and easy thread locker. And if your break a bolt removing a water pump or thermostat or hub bearing don’t blame me.

I’m not an advocate of using any type of additive including Loctite on any application with critical torque values. Additives affect the torque, and that can easily interfere with the proper function of a self-locking nut.

Vehicles subjected to extreme vibration often use safety wiring. The heads of the bolts and nuts and connectors are purchased drilled out to accept steel-carbon safety wire applied in such a manner that the screw or nut cannot turn counterclockwise. Aircraft use this same technique; Everything on our B52 bombers was safety wired to prevent loosening. Recognize that in the 40+ years since I was on them, new types of fasteners have been developed to reduce safety wiring, but safety wiring was the standard then. Dragsters used to use the same techniques of safety wiring. Don’t know what they use today.

Stay away from red unless you don’t want to ever get off again. Motorcycles locktite because of the extreme vibrations

I’ve used the gasket stuff on water pump bolts and that worked well, but most of the nuts you are talking about are lock nuts if you use new ones. You should use new nuts. The axle nut for example is a single use item. Just IMHO.

The only thing I use Loc Tite on is critical internal engine parts; or transmission all depending.

Depending upon the car I sometimes use Loc Tite or a sealer on some flywheel bolts, some head bolts, etc as they may protrude into the crankcase or water jacket of the engine block.

thanks everyone so much for the advice!! I was just paranoid and now I feel better. makes sense if it didnt have loctite on when I remove bolt to not use it to put it back on. awesome!

Hi

I just had my front shock absobers replaced, some bolts were opened (don’t know the names) in the process, so do these bolts need Loctite?

No.they do not.