My Dirty 4 Door - Daily Driver content

[Jean]

Just spent a couple hours on figuring what the fuck is making the rear end noise today in 107F heat.

I've removed everything from the trunk , double checked that it wasn't the spare tire or the battery, it's not, removed the spare tools/jack.

I've now rulled out the exhaust. I've also checked the axle bolts and the rear shocks and the rsms, and the springs, everything is tight. I've checked the sway bar mounting hardware as well.

The noise is happening when I lower/raise the car off the ground with the jack or on the lift. I am now being able to duplicate this by opening the trunk and if I seat in the trunk and push it down/up the noise is coming from under the car, and it's pretty damn loud. This noise is present when driving at low speeds, especially pulling in/out of parking spots. When driving at speed over manhole covers it sounds like the trunk lid isn't closed all the way, it's that loud and I can almost feel as if the rear end looses traction for a split second.

I've went ahead and did this -

-put the car on the lift, used a pry-bar to move the diff up/down in the subframe (no noise)
- just in case I've also tried pushing the diff UP as far as it goes in the subframe and then tightened the 4 bolts in the rear bracket the hold it, noise still present when I bounce up/down on the trunk of the car.
- did the same as above but let the diff "drop" in the subframe and tightened it then, same deal.

So the noise is not coming from the diff either, I would LOVE to know what is the correct way to tighten the diff mounting bolts, should the diff be at the HIGHEST point in the subframe, in the middle or at the lowest?

I then did the same thing with the left/right big subframe mounts, I've loosened the nut on each side, then also loosened the 13mm bolts and let the car sit on it's own weight and then tightened the left/right nut as much as I could. Then tightened the 13mm bolts.
This still didn't get rid of the noise, but I think it did decrease the amount just a tiny bit.

I am not thinking this is where it's coming from.

I've used the mirror and a flash light to check for any gap between the subframe plates and the diff bushings, none present.

Is it possible that something is up with the actual "bolt/rod" that goes through the body of the car? I did not have to do anything with that threaded bolt/rod when I lowered the subframe, the bolts stayed in the car.

[GDA]

Nice work.

I did not see you mention how you torqued the dog bones (car down and on level ground) and the cross brace on the passenger side.

Upper rear E34 springs on M5s are known to crack with high miles... are both springs all properly seated in the perches?

[Jean]

Video of the noise- http://www.r3vlimited.com/board/show....php?p=3312975

Nice work.

I did not see you mention how you torqued the dog bones (car down and on level ground) and the cross brace on the passenger side.

Upper rear E34 springs on M5s are known to crack with high miles... are both springs all properly seated in the perches?

I didn't torque the dog bones or the passenger rear cross-brace on the ground, only the trailing arms since the shop manual called for that.

I can re-torque the dog bones (or remove them I guess while troubleshooting this, since all they appear to do is limit the trailing arm "droop").

The springs are H&R sports, no rust and are seated correctly from last install.

[Jean]

That rear suspension noise is gone, it was due to the pitman arms/dog bones that went bad since I've installed them last year....

I am only buying Lemf. parts from now on, good thing I did for all of the rear end and front end (the 2nd time around).


----------------------------

This morning on the way to work it was silent, and as the car sat in the parking lot as soon as I left it started making these noises.


After work went to a shop while it was making these awful noises and put it on the rack, disconnected the dog bones and noise is gone. Pushed the car down a few times, it's silent and smooth. Just got home after driving it for about 10 miles, these noises are 100% gone. I'll report back tomorrow as well once it sits overnight and all.


I installed new dog bones right after I bought this car, so I think they "might" still be under warranty. Right now I am just driving w/o them as all they aren't critical, it's the same suspension as on e30, plus these dog bones that limit the "droop" for the trailing arms. I'll install new ones next week still.

[Jean]

For those of you running coils on e34s, what are your spring rates and how is the ride quality over road imperfections at slow and fast speeds?

I am going to be sending Billy Sports for a re-valve as the right quality plain sucks over pot holes or speed bumps etc... it's on H&R Sports.

[Jean]

So after 8-9 weeks of waiting I got my custom revalved front/rear shocks from Bilstein. Also Blunt provided new H&R Sport springs, should be installing this hot mess this weekend!

And, few weeks ago spent about $500 on getting the car to pass smog. Replaced all top end gaskets/hoses, o2 sensor and new cat. One of the wheels needed to be fix as it was a little out of round, and now riding on BFG Sport Re760s.

Hopefully I'll be a night and day difference in ride quality with these shocks and springs.

[Jean]

What a night and day difference! Was worth the wait, no more clunking noises from the back when going over bumps. Car is so much more fun to drive now too!

Weakest link now is steering play and of course lack of v8 power lol.

[Jean]

How much shall I ask for it, 212k on the chassis...but maybe 1-2 years at most on all the parts I've replaced.

billy sports
h&r sports
all suspension parts front and rear replaced with oem lemf/meyle parts.
staggered wheels e38 wheels.
bf sports tires
new blower fan and resistor
working a/c and heat
m5 front sport seats, no rips.
lukes e34 sub box with 12" kicker sub, 4channel amp, cd player and front components.
e60 short shifter, m knob
m5 front console.

month or so ago replaced blower fan and resistor with brand new oem parts.
just did front brakes, pads and rotors
2 year old cat and new o2 sensor
new oem crank sensor
new oem clutch fan

lots of scratches and dings on body lol.
may need wheel bearings or hubs
2nd gear synchro is bad.

engine replacement in progress for a lower mileage m50vanos from 95car.

Would $3k be fair?