How do you.....?

[kev131]

How do you buy a second hand back axle for a 131?

In other words... are there any checks that you can do to make sure that the insides have not been minced at some stage...? Is it a "trust your instincts" purchase...?

[stathe174]

Basically it's a trust your instincts thing... But you can check if it has signs of licking valvoline in the cap and for some signs of rust... But keep in mind that is at least 27 y.o. part...

[djape1977]

noisy diffs are a common problem on lada's so i'll say i have some experience on that one. i guess that's the reason why you're bringing up this topic?
diffs get noisy when driven with no oil, or too little of it. usually one of oil seals fail and oil leaks out, leaving dry gears and the result is inevitable...

1. look for axle that's dirty, dusty and muddy but not greasy. if dry, it means that there was no oil leaks. if dusty and muddy means that it wasn't recently washed to make it look pretty for sale. greasy axle is probably worse then one you already have.
2. if axle is on the car, lift one rear wheel, put gearbox in 1st, try to rotate lifted wheel by hand, one way, than another in short motion. no klanking noises should be heard even if jerked one side to another. if axle is off the car, do same test but you need to block input shaft by one hand and. same applies as if axle on the car. in both cases, there must be some  "free" turning possible. how much? the less the better. try to compare with axle on your car.
3. check for play in the bearings. try to jerk up and down. if any motion - bearings are busted. this has no relevance to the diff but can be a source of noise and is a pain in the ass to replace.
4. if possible, remove the back plate covering the diff. look for any corrosion on the gears. if more than few specs of corrosion are present - walk away. this is ussually problem with axles that haven't been driven in a long time. 10yrs or more
5. rear axles from 132/argenta are pretty much bulletproof. i've never heard a noisy rear end in any 132/argenta and i've had/driven/worked on many over the years. once i had a halfshaft bearing on my 132 2500d fail but that was when the car had over 400.000kms on it's clock. i never tried, but from what i see, 132/argenta rear end can be easyly modified to fit 131. maybe that's the best way to go?
6. don't forget diff ratio! diff from a car with same size engine is most likely to be with same ratio as yours.

[kev131]

Hey - Those are some very useful pointers for a non mechanic - Thanks Djape.  What tools are needed to remove the plate by the way?

Luckily I dont need one just yet - Both my back axles are behaving very well at the moment but as my Sport is a "keeper" ...I like to have parts "in stock" to guard against the future date that disaster may strike.

[djape1977]

you might say i'm quite good mechanic for a locksmith 

don't remember exactly but it's 10mm socket wrench or 13. not a big job to remove.

you might want to consider changing a diff ratio when you're at it.
shorter diff (from 1,3 or 1,6 will give much better acceleration but lower top speed and higher highway revs
longer diff (from diesel or volumex) will give slower acceleration wit lower highway rpms. i guess the top speed wouldn't be increased since you can't get the engine to max revs in 5th even with factory installed diff.

all depends on your driving style and needs. i like to keep diff ratio as short as possible in my "town car". less shifting is necessary and aceleration is much better. in lada i have a 2,0 fiat dohc, 132 gearbox and 4.3:1 lada diff. starting from 2nd gear is as in 1st on 131, and then i just floor it up to 80km/h. i can drive in 5th from 30km/h up to 170km/h, and in 3rd from 5km/h up to around 100km/h

one downside to fiddling with diff ratios is that speedo is not going to show true values. the speeds i was talking arout are read from GPS

[miro-1980]

In keeping with previous remarks - buy one from a diesel !!!

Miro

[kev131]

Here is a picture of the axle that I'm considering. To my untrained eye the corrosion on the outside would indicate many years of non use - Would this mean that the insides are similarly rusty (and therefore of no use) or if the no grease/oil on the outside theory being a good thing, maybe the inside is still protected from rust as it is still full of oil.

The accompanying engine - They both look like they have been used as anchors!

[david]

I would look at the spring seats on the outside as they are the first things to rot out and they look bad from the picture tap round them a few times and knock off some of the rust and see. I generally turn the flange back and fro where the propshaft bolts to the axle and if it feels smooth and not to much slack or any bad noises they are usually ok. wouldnt hold out much hope for the wheel bearing looking at the condition of it.  It also looks from the picture that its a mk3 131 axle which are slightly wider than earlier type but still fit.

[djape1977]

be sure to remove the back plate from diff and take a look inside. if it stood in the same position for years migh be that gears inside are ok on the part that was submerged in oil and corroded on the part that was above oil

as i can see on the photo, axle was removed by cutting of shocks and panhard rod??? 
that would be the first, even for me