Loud 'popping' from front end

[metalmonkey47]

I thought I brought this up here before, but maybe not.

 

 

Anyways, I've had an issue the last 8 months I've owned my truck, but I've been through just about everything and still haven't traced down the culprit.

 

It ONLY happens after I park the truck and let it sit for 10 minuets or so. When i get back in and drive down the road, I get a loud POP that sounds like it's coming from the front passenger side of the truck. I've already replaced the caster rod bushings and inspected and adjusted the brakes (which were new when I got the truck.) When it pops, I feel as if the brakes are dragging. This has been a more recent symptom of the issue. I've been through everything on the brakes and haven't found anything that would suggest it's brake related.

 

For the sake of it, I checked for any obvious wear in the wheel bearings and control arm bushings and didn't find anything abnormal.

 

 

 

I'll take it for a drive tomorrow and record a short video so you can hear what I'm hearing.

 

It's not very serious, but it's getting to the point that I just want to go ahead and get it over with.

Edited May 19, 2012 by metalmonkey47

[datzenmike]

Does it pop as soon as it starts to move or later down the road?

 

Next time it sits that long try bouncing the fender up and down on that side. See if it does it with that.

 

If not, jack it up and try to spin the wheel by hand. Is it tight?

[metalmonkey47]

It doesn't pop as soon as you move the truck, and used to be that it only popped when you hit the brakes the first time. Now it does it occasionally a few hundred feet rolling if you haven't hit the brakes yet.

 

It doesn't make any noise rocking around the front end, and the tire doesn't drag anymore then normal. Part of me thinks it's got to be brake related, because I can feel the truck slow down once it stops. Almost as if it's braking better, but perhaps it's something else causing that.

 

Is it possible the wheel bearing is loose?

[ggzilla]

Doesn't seem like a familiar problem. Wheel bearing is unlikely.

[Edz280zx]

Maybe unrelated, but my Z did the same thing only from the rear. Ended up being the shoes sticking. Might even be a wheel cylinder going bad...don't know if you have drums on the front or not.

[metalmonkey47]

I do have drums up front, but I've got new wheel cylinders on all 4 wheels.

 

I should probably just go ahead and throw $$ at shoes and hardware, although I'd rather just diagnose it first.

[Edz280zx]

yeah, I understand that....it's always annoying when you can't find a "mystery" sound..lol

[ggzilla]

Just remove the back wheels and inspect. Maybe a spring is loose.

[MikeRL411]

You really need to grease the front suspension lubrication points! Get out the grease gun and wipe off the zerk fittings. I'm sure that the suspension will thank you and it just may quiet down the creaking and popping.

[metalmonkey47]

Here's my popping. You won't hear it until about 0:46 when I apply the brakes.

 

http://www.youtube.com/watch?v=5hotzjHCGG8&feature=youtu.be

[ddrum]

when you press the brakes it makes a popping sound right? and then the truck feels like the brakes are dragging? this happens to my truck and it is because of my wheel cylinders (cheap Oreilly's quality) . The small cylinder inside the wheel cylinder pops out when i hit the brakes hard and they kinda get stuck for a little while.

[datzenmike]

Front drum? I wonder if the shoes are on backwards? Sounds retarted but there are leading and trailing shoes. If properly installed the forward motion helps pull the shoes against the drum. Don't ask me which is which but check this out with someone who knows.

[LaidoutRivi63]

are the flex lines old? I had a 58 ford station wagon that had a bad flex hows for the rear and it would lock pressure in the rear brakes. could be something independent to that side

[metalmonkey47]

I'm gonna come back and answer questions in a little bit when i have more time, but ever since I greased the suspension/king pins as MikeRL411 suggested, it doesn't seem to do it as often. In fact, I don't seem to notice it at all anymore. The steering is super responsive too.

[datzenmike]

King pins? Oh yeah. That's likely it. (former 521 owner, I know about king pins)

[metalmonkey47]

I've been hoping that wasn't going to be an issue. They look like they're a pain in the ass to replace. When i greased them, it spit the grease out the top and bottom of the spindle so I'm going to have to do that soon.

 

Same with control arm bushings.

 

I'll just read more into the ball joint conversion.

[datzenmike]

Grease out the top and bottom is, I think, good... it means at least that the grease is getting there. My 521 would often not take any. I heated the king pin with a torch once and pumped the grease and smoke came out but I got the grease in. The king pins were like old rusty hinges. A night of partying in the mud holes and the steering was always better the next day from the water getting in there. Swore I would never have another king pin truck.

[metalmonkey47]

Okay, then I'll take the grease coming out as a good thing.

 

Would it make sense to pump some extra grease through the king pins to flush out some of the old stuff??

 

 

 

Also it's confirmed!! This was the issue. I have NO more popping at all coming from the front end. Kinda scary how responsive the steering is though.

[ggzilla]

You do not need to "flush" the grease.

 

Great to hear it is fixed. Glad my pickup has mcpherson struts, low maintainence.

[MikeRL411]

Glad to hear that grease was the answer. You need to pump in enough grease that the old stuff squirts out the end seal fitting furthest from the zerk fitting, that's the way these old time fittings work. The initial residual squeeking was most probably some residual rust particles wearing down. Regrease in a month or so and you will likely see some brown or red color flecks. A quick wipe with a rag to clean off the old grease that squirted out and your garage floor will love you. My car is 45 years old so I am familiar with the need for routine maintenance.

 

Now if only I could find some of the old woven polyethelyne grease discs that fit in pockets in the end of the rear leaf springs my 411 would be quiter than the day I bought it.

[metalmonkey47]

I hate to say this, but THE NOISE IS BACK with worsening symptoms:(

 

This may or may not be related, so I'll let you decide. The noise came back and now I'm hearing it from both sides. When I get the nice 'pop' I can feel the truck start to decelerate.

 

 

NOW, since lubing up the front end, I've noticed that the front end likes to 'walk' to the right when I let off the gas pedal and occasionally just driving around. It does it worse at high speeds and YES I checked my lug nuts. Coming to a stop at low speeds, I hear a loud squealing that's almost certainly the brakes.

 

 

I feel like my brakes are probably dragging, and I have a feeling you'll probably agree, but we'll see.

 

It's strange that this has started to become an issue suddenly.

[ggzilla]

Have you taken the wheels off and checked the brakes yet?

 

Any chance it's a backfire, and not something from the suspension or brakes?

[metalmonkey47]

Have you taken the wheels off and checked the brakes yet?

 

Any chance it's a backfire, and not something from the suspension or brakes?

 

I have not. I'm off all day tomorrow, so I'll have a chance early tomorrow.

 

No way it's a backfire, I can feel a drag as soon as it does it. It feels like it's in the brakes, which is why I was surprised that it stopped when I greased the king pins.

[erichwaslike]

well if you feel the need to replace the drums adn kinpins with balljoints and disk ill have my conversion coming out soon for all kingpin datsun trucks. if you are ill let you know when they are up for sale