ATC529R

I can't give previous info about the rear end as it was acquired for the build. It's an 83 or 84 out of GSL-SE I am fairly sure. posi-tration, disc brakes and such. It also has moser axles, but I sent them an axle when I had them make mine, so I would think those are cut properly.

I get a clunking/metal on metal sound on slow right hand turns. not a constant sound.....more of a clicking, but a big click if you get my drift. bearings/axle is solid...no play etc. The car drives fine other times. I can lay into it from a dead stop no problem and get posi and light the tires up. I inspected, visually, the internals when I got the rear end and all looked good. I need to drain the diff and check they fluid for metal, just curious if anyone elsecould ad input.

Does this sound like something bad????? pinion, spider gear etc. any info would be appreciated.

rxtasy3

iTrader: (2)

the gsl-se is 84-85 only with large axle shafts and 4x114.3(4.5) lug pattern. 83 gsl will be small axle shafts and 4x110 lug pattern.

GSLSEforme

None of these parts are new,except your axles,everything else has been in service a long time. Since you have Moser axles,you"re "using" the car. Might've been a good idea to disassemble differential when you got it and inspect it knowing your intentions.
Noise could be chipped pinion,spider gear,carrier damage. After you drain oil into a container,run a magnet around in it and up in differential housing looking for shrapnel. Remove axles and look closely at splines compared to oe axles. Measure Moser axles against your originals.
Before you pull differential,try original axles in place of Mosers. Have to ask,oe wheels,are they tight? Correct wheel studs pressed flush in axles? Mosers don't have hubs on ends so lug nuts doing double duty.

ATC529R

Wheels are 16 “ with 245 on them and they have wheel spacers. So you might say they’re doing triple duty or so as to flex if that is what your referencing. Never thought of that. Also it’s a 3.909 gear, same as my 1980 which I still have and might be able to use something from it if there is something in the chunk. I did disassemble and it looked good.. better double check those spacers and lug nuts for tightness. It’s only slow almost dry right turns under power.

Carl

iTrader: (2)

Could just be the clutches in the LSD shuddering when the LSD is doing its thing on a slow,sharp corner. You could try adding some limited slip additive which makes the clutches a little slippery and should get rid of the noise. That has happened a couple of times for me after rebuilding the LSD on my race car.

Rx7fb spirit r

I got the same problem on my car.The spacer lost a little lenght and produce the noise in the turns. I ignore the noise for years without any issue. Last year the noise was coming louder and i changed the 26 spline diff with the torson ll out of a miata.

Spacer

ATC529R

Thanks for the advice guys... gotta look into this as I don't want it to get to be real bad. just wierd that it's on hard slow, almost dry right turns.

LongDuck

Am I the only one who doesn't know what a "hard, slow, dry right turn" is? Issat opposite of a soft, fast, wet left turn?

rxtasy3

iTrader: (2)

<30 mph, then jerk the wheel to the right and it's not raining. hard to say tho if it was cloudy or sunny.

Carl

iTrader: (2)

To check whether the LSD clutches are causing the noise, jack one side of the rear end up and try turning the lifted wheel. If it is really hard to turn, the clutches might be adjusted too tight. I think the breakaway torque should be 30-50 ftlb. Also if the wheel kind of jerks as you turn it, it is a sign that the clutches may be chattering. The wheel should turn with resistance, but relatively smoothly.

ATC529R

Thank you for that. I will check it out.

A slow dry right turn is when you let it roll back out of your driveway and drag your no power steering's car's wheel to the right while trying to be nice and ease onto the throttle cause you don't know what the hell the clicking noise is, but know it aint good.

Carl

iTrader: (2)

If the clutches are chattering, you basically just need to add some limited slip additive.

flycasta

iTrader: (3)

Did you just start driving with it recently? if yes, the plates can fuse together a little and making them slip can be a little clunky.... figure 8's and LSD additive should fix the problem.

if no..... then check the axle length...... put some whiteout on the ends of the axles, drive a bit and remove them... if the whiteout has been removed or scrapped then the axles could be a little too long and hitting the cross inside the LSD...... grind down to a desired length.

If no..... what oil are you using.... most calls I get about LSD's being noisy are due to the oil...... seems that an 80W/90 is not good enough and it really needs to be a mineral only oil..... not blended or Synthetic 80w/140 potentially with an LSD additive as well.

I have had other issues bought to me but either of those 2 is generally the cause.

GSLSEforme

This can be prevented by using crush collar eliminator,a shimmed solid spacer,maintains proper pinion bearing preload.Hard acceleration,big tires,slicks can deform crush collar further than original pinion bearing preload dimension causing no preload and negative preload...ring and pinion wear is accelerated and incidence of breakage increases the longer diff is run in this condition. Any differential that adjusts pinion bearing preload using a crush collar will have lessened measured pinion preload within 1/2 dozen drag strip launches on a fresh setup.

GSLSEforme

Don't understand this as a fix...the LSD is supposed to have friction modifier added on each differential oil change or setup. Cars originally came with it. Adding more in attempt to fix noises is futile.
Symptoms that can be alleviated on these cars with a gear oil change with friction modifier are groaning and crabbing on turns. Synthetic 80w90 hypoid+ modifier is best for these diffs as it is for all clutch type LSDs. If you want more clutch bite use mineral 80w90 hypoid oil with modifier.
Torsen diffs should be run on mineral hypoid oil to work best. Synthetic will do no harm but axle lockup will be a lesser percentage and delayed. New big hp tq trucks that come with these diffs are running synthetic hypoid in order to help other components live longer.

ATC529R

my gut says I should pull that drivers side axle and grind it down a little. FWIW


Thank you guys for the info on in this thread. very enlightening. I forget the what lube I used, as it's been a couple years...and yeah recently got on the road. I'll get the additive and run some figure 8's though.

you saying that made me laugh because I had my kid in the car and she wanted to to a couple donuts......no problem I say....lol (and yeah I know how to do donuts) but I did em in 2nd and almost lost it stopping just shy of having an issue I'll just say lol. Did it again more mildly in 1st gear for fun afterwards and more controlled. I really see what you guys mean about the factory sway bar making it twitchy!!!!!!!!!!!

just can't put parts from 8 different cars and expect it to come out new I guess. lol.

ATC529R

I checked this and it's good.

after looking more at how the rear end works via model, it has to be a/the spider gears......probably from some donuts I went crazy on early on.

I have a 1980 rear end sitting there, same gear ratio. 3.909. will it have the same spider gears so I can just swap em out....or does it even have em cause it's not LSD. thanks

It lights em up going straight, only in turns, and it's louder than a shudder....not that bad yet though to where I can drive it.

Carl

iTrader: (2)

Is there any in and out play on the axles? I have had the pressed on collar that holds the axle bearing in place slip a little, allowing the axle to move in and out somewhat. In one case, this allowed the rotor to rub on caliper bracket (or some combination of things rubbing). It was on a racecar, so we weren't paying attention to noises (which we probably could not have heard anyway over the exhaust). I assume it made more of a grinding noise, but it is pretty easy to check if there is in and out play. Just a thought.

Carl

ATC529R

nah, no play... I just had the wheels off etc and checked it all while working on E brake setup and making sure that was not interfering on either side.

kirkosaki

After swapping my rear end (LSD form an 83 into my 84 GS). I noticed a slight whining noise on accel and decel. I have the Techno Toy rear trailing arms installed.. Is my Diff not set up properly or is this normal? Thanks!

mustanghammer

iTrader: (3)

My guess is that you are hearing this because of the T3 control arms. The rod ends in the control arms won't dampen rear end gear noises like the OE rubber bushings or even Poly bushing do. Ran into this on my Fox Mustang when I installed lower control arms that has poly bushings on one end and spherical bearing on the other. Car handles better but now I can really hear the rear end.

Of course it could also be that the gears weren't setup correctly but normally in that situation you will hear noise on either decel or accel but not both.

ATC529R

I did o through this rear end, and change the outer plates, forget what they are called.... also checked tolerances and all .....it was a while back

Seems the rear end additive is what really made a difference after putting it all back together. sounded about the same, then added the additive and the sound improved. going to add another bottle hen I drive again, but the car is down right now with a fried clutch,