Causes of Guibo failure?

[Ellie]

I had a mechanic warn me that my guibo had cracks in it and would need replacing. I left it for about two years and it was still in the same condition when I had my gearbox rebuilt by a different mechanic. He said the same thing and really recommended I change it. So I had it changed. About 6 months later the new guibo exploded.

So a couple of questions. Other than the new guibo being old, hardened rubber, are there any other causes that would have put strain or pressure on it to disintegrate?

When reaching a speed of about 60mph there would be a very loud whack sound come from underneath the car or the trans tunnel. It sounded like I'd driven over something that had flicked up and smacked against the floor pan. Any suggestions as to what and why this was caused by?

[So Cal Mark]

sounds like it wasn't installed properly

[djape1977]

124 owners have a fortune and missfortune of having a car that shares lots of oily bits with lada.
since millions of ladas were made that use exactly the same guibo as 124, it's more then likely that any new guibo you find will be a lada part, not fiat. in itself, this is not a bad thing. original lada parts last as long as fiats. problem is that every parts manufacturer in the world makes parts for ladas. many of them make shit quality parts. retailers don't necesarily know what they are selling.

[Ramzi]

The U.S. In many cases not only requires the country of origin but also a factory of origin.

[djape1977]

don't get me wrong Ramzi, and others who make their living on selling parts, i suffer same problems in my daily job.
right now, at my workshop, there are two ladas, one fiat 125 and one seat 124

unfortunately, i found that quality of aftermarket parts varies wildly even from batch to batch from same supplier.
other problem is fake origin of parts or fake brand. i've seen many "OEM" lada parts that have clearly nothing to do with AvtoVaz, even though the paperwork and packaging seem legitimate.
other extreme example is "Master Sport Germany" brand. name leads customers to believe it's a German brand, which implies quality. however, it's a german registered company that sources it's parts from various Chinese manufacturers. quality of their products varies from completely useless to decent. i found that it's best to avoid it all together.
parts "made" by master sport that you might encounter in 124 market are for example
guibo
steering idler
ignition lock
gearbox bearings
brake hoses

[Ramzi]

Vetting the parts one sells is critical. And any supplier who does not do their homework before offering an item for sale is a fool.

[baltobernie]

Other than the new guibo being old, hardened rubber, are there any other causes that would have put strain or pressure on it to disintegrate?

If the center bearing carrier is shot, there will be lots of wiggle in the driveshaft, which contributes to premature guibo failure. Ditto bad U-joints. Next time you replace the guibo, inspect the entire drive shaft assembly.

[Ellie]

Thanks all for the conversation. I was concerned that there might be something more sinister going on with the driveshaft that unnaturally stressed the guibo so the comments about the center bearing and U joints will be taken on board. Hopefully the 2nd new one will survive and I wont need to explore it further...for the time being

[rridge]

The driveshaft yoke that rides on the transmission output shaft must be free to slide in and out on the splines of the output shaft as the rear end rises and falls. If the yoke is binding the driveshaft will feed lengthening/shortening forces into the rubber donut. There is a grease nipple on the yoke but if you are replacing the donut you can remove the yoke, clean the splines, and then lightly grease them before reinstalling the yoke.

Richard

[RRoller123]

How much grease should that fitting take? It seems to just keep accepting more and more, with none leaking out anywhere to indicate that it is full.