Strut top nut removal

[JHZR2]

I've seen two concepts with the topic of removing the top nut from a strut to get its mount off.

One is that you must use the right tool, or at least a vice grip around the strut shaft to prevent it from turning, because the shaft turning will overheat and damage the seals in the strut gas cartridge.

The other is that an impact gun should be used to get these off, just doing a few hits at a time, and going that way is no big deal.

What's the truth? I've been watching youtube videos, so up you know how that goes. The guy in the autozone movies used an impact, the guy from the Netherlands in the euro. Monroe videos uses a special tool. I've read and seen mixed suggestions elsewhere.

I'm ok with buying a tool, even a pricy one, if it is usable for multiple cars, and I'm investing in a good spring compressor because I'm sure that much first strut job won't be my last....

But not sure how different the nut removal job is from make to make.

Recommendations?

Thanks!

 

[spasm3]

On the struts i've done, i used a drop end wrench and a an ajustable wrench or some were a recessed allen head. I would not use a vise grip on the new strut, the scatches could cause it to leak, pull in dirt.

http://www.twinsaabs.com/9-5_repair/suspension/front/step2.asp?nsteps=4

 

[The Critic]

Impact for removal.

For re-install, I install it finger tight, re-install the assembly in the car, then fully torque the top nut to spec. At least that's how the Toyota FSM wants it done.

 

[Chris142]

I worked at pep boys and then a goodyear tire store and we just buzzed em off with an impact

 

[Zaedock]

Impact gun. Zap off, zap on.

I recommend a spring compressor that uses plates instead of hooks. It's much safer/faster.

 

[jaj]

It depends on the strut design. A Bilstein and many single-tube struts are inverted, and the outer body of the actual damper assembly is the "shaft" and it's got a welded stud at the top that connects the upper strut mount. They're pretty rugged.

Others, like Koni and most of the twin-tubes will have the shaft attached to the upper mount and then go down through the damper and have a piston and valving mechanism bolted to the bottom. These aren't so rugged.

The risk with using an impact wrench is that while you're unthreading the top nut, you might also be loosening the valve retainer nut at the bottom of the shaft. The damper will fail if this nut comes off.

I use a damper nut tool - 21mm and 22mm hex openings that has an open center to pass a socket through to hold the damper shaft. They're cheap and they prevent any damage to the guts of the damper while you're undoing the nut.

 

[KB2008X]

The majority of struts I've dealt with over the years come apart best with an impact.

 

[Ndx]

Open end ratchet + Allen key
A lot OEM says no to impact (,yes I used it on my cars but if possible I wouldn't )

 

[E365]

I installed some Bilstein HDs on my BMW many years ago and I think I made a tool. If I recall properly I bought a cheap socket, ground flats at the base and used an open end wrench to turn the socket. Then the socket was open to hold the shaft with an Allen.

The nut must be recessed which meant I couldn't use a box end.

 

[Pop_Rivit]

When I've done them in the past I've just used an impact. Quite simple.

 

[JHZR2]

Interesting. So mixed info and recommendations here too.

Seems like impact is not the right way, but works for most/all...

 

[JHZR2]

Originally Posted By: The Critic
Impact for removal.

For re-install, I install it finger tight, re-install the assembly in the car, then fully torque the top nut to spec. At least that's how the Toyota FSM wants it done.


But the fundamental issue is preventing the strut shaft from turning. Did you use a special tool?

Also for all the danger and safety considerations of compressing springs, since that top nut is all thats holding the clamped spring down, is finger tight tight/safe enough? Id be worried myself if the nut wasnt on and torqued to spec...

Have to consult FSM but Ive watched enough "how tos" to see that it can be done many ways, though it does not seem that all are safe/right... I like the idea of finger tight then torquing when loaded down, but not sure if it is safe.

 

[tommygunn]

This is why I like quick struts

It's just too bad every car with struts doesn't have one available!

 

[IndyIan]

Originally Posted By: E365
I installed some Bilstein HDs on my BMW many years ago and I think I made a tool. If I recall properly I bought a cheap socket, ground flats at the base and used an open end wrench to turn the socket. Then the socket was open to hold the shaft with an Allen.

The nut must be recessed which meant I couldn't use a box end.

This is what I had to do as well with the Neon, but used a 1/2" drive deep socket and then put a 3/8 drive extension through it with the right socket on it to keep the shaft from rotating.
Just used the angle grinder to make the flats.

 

[threeputtpar]

When I did the fronts in the Audi, I tried to use a locking pliers with a piece of rubber in the jaws to hold the shaft but it was a failure. I used my cordless impact to get them off easily and also used it to put the nut back on. I just took it easier on the install and once the shaft started to spin, that was where I left the nut.

 

[dnewton3]

Originally Posted By: tommygunn
This is why I like quick struts

It's just too bad every car with struts doesn't have one available!

Amen to that! I like them too, but I've had to do without due to limited applications.


As for the topic question; I've done both ways. If there is a shaft slot for using a tool or such, and turning the nut with a wrench, I'll do it. But I've also used an impact on many, and never had an issue with any damage or seal failures.

As always - caution of sudden release of spring force is the safety topic to pay most heed to.