What goes wrong with Fendt vario box ?

[Spotty Dog]

How do Fendt transmissions fail ? Do they just go bang and stop or do they develop a problem gradually ? My 828 has started to 'surge' a little going up hills on the road hauling silage. Feels tranmission related rather than engine.

 

[Chae1]

@Treemover knows a lot about them if I remember correctly.

 

[Treemover]

Cant say I'm an expert. I sold my 818 a good few years now, so its all a distant memory. For what its worth, I heard no bang or pop. I just lost drive, and it straight away threw up error codes. For a year previous it was throwing up a blocked filter code, but everyone (dealers) told me the sensors gave trouble, and if the filters were changed it was most likely nothing. When they replaced the vario, I got no vario or filter codes. Make that what you will.
Have you looked at the vario pressure settings?

 

[davedb]

Bloke I talk to a bit and @CrevisbigX has a fair bit do with him says the swash plate linkage can wear and cause surging and eventually error codes there’s a range of things that can happen from pipes bursting to the bearings failing could be anything basically

have you tried calibration on yours? @Spotty Dog

 

[kiwi pom]

Cant say I'm an expert. I sold my 818 a good few years now, so its all a distant memory. For what its worth, I heard no bang or pop. I just lost drive, and it straight away threw up error codes. For a year previous it was throwing up a blocked filter code, but everyone (dealers) told me the sensors gave trouble, and if the filters were changed it was most likely nothing. When they replaced the vario, I got no vario or filter codes. Make that what you will.
Have you looked at the vario pressure settings?

Dealers told you to ignore a blocked filter code? Wow. No wonder manufactures are always having dealer shake ups.

 

[Lewis821]

I know of one that had a bearing go on a small gear which then dropped into the box causing a big bang

 

[kiwi pom]

How much does the bit behind the steering wheel have to do with it?
You'd think with all the sensors and stuff on them now they wouldn't allow abuse but...

 

[Cowabunga]

Dealers told you to ignore a blocked filter code? Wow. No wonder manufactures are always having dealer shake ups.

They do have a filter sensor that can cause an amber warning light after a time delay and then some time later when the oil has warmed up, a fault code.

I changed the sensor myself, but it made no difference, At a subsequent transmission oil and filter change I found the the big filter that fits behind a cast plate through the side of the gearbox was not seated quite correctly or that the large O ring was slightly damaged. New filter fitted and there's been no hint of a problem since.

If there is some degree of hunting, turn the transmission setting so that the engine lugs down to about 1500 rpm before the transmission ratio downchanges. Any slight hunting in the transmission should be completely eliminated if the transmission is healthy.

 

[Shep]

How much does the bit behind the steering wheel have to do with it?
You'd think with all the sensors and stuff on them now they wouldn't allow abuse but...

My neighbour/contractor buys a few fendts, on a factory trip they were told that the biggest problem with the vario was the bit between the steering wheel and the seat.
But then they would say that wouldn't they.

 

[Cowabunga]

My neighbour/contractor buys a few fendts, on a factory trip they were told that the biggest problem with the vario was the bit between the steering wheel and the seat.
But then they would say that wouldn't they.

They would indeed, because there is very little that the driver can do wrong with this transmission. Over revving the engine is about the worse thing, which can happen if speed passes 53kph down hill by going over compression. The transmission can then change down ratio rather suddenly, pushing the rev counter round the clock. This is NOT good, but for the engine mostly which could possibly drop a valve or something I suppose.

The main thing for the driver to watch with the transmission itself is to ensure that draft work and general field work is mostly done in low ratio and not in high. That's is really. Otherwise it is nutproof.

 

[Ormond]

They would indeed, because there is very little that the driver can do wrong with this transmission. Over revving the engine is about the worse thing, which can happen if speed passes 53kph down hill by going over compression. The transmission can then change down ratio rather suddenly, pushing the rev counter round the clock. This is NOT good, but for the engine mostly which could possibly drop a valve or something I suppose.

The main thing for the driver to watch with the transmission itself is to ensure that draft work and general field work is mostly done in low ratio and not in high. That's is really. Otherwise it is nutproof.

That I wouldn't agree with......drivers have a big part to play in any machine e big or small....complex or simple. I agree with you on the over reving the transmission down a hill and over heating the transmission by doing heavy work in range two.....another couple of things....always always come to a complete stop when changing between ranges.....pulling back on the level to slow down to with a heavy load I don't really like. It's amazing
How a driver can reduce speed by backing off the throttle in advance rather than hammering up to a turn.....yanking back on the vario lever to slow down and heavy use of the brakes.

 

[daveydiesel1]

Friend fixed his vario 924 couple years back. Big main pipe had blew of and dealer was wantin 16k for replacement tranny so he decided to open the box and saw the main pipe for forwards had broken of. Same tractor needs a new stepper motor currently

 

[deleted user 837354]

I am confused. Why would you try to do heavy work in the 2nd gear? Isn't gear 1 fast enough or something?

 

[Ormond]

I am confused. Why would you try to do heavy work in the 2nd gear? Isn't gear 1 fast enough or something?

Range 2 for road work mainly...range 1 tops out at 25kph....forgetfulness the biggest cause

 

[ColinV6]

Having only driven a Vario Tractor for a few days, (autocommand), I found slowing down from speed the single most unnatural thing and the only thing I didn’t like about the gearbox. No matter how I tried it always ended up with loads of revs piling on. What is the correct procedure?

Things like the above overspeeding down a hill also? Shouldn’t there be a engine/gearbox limiter to prevent this?

 

[zealman]

I had a 920 which was the first vario to fail in the southern hemisphere so I was told. Over a period of a month or so it got harder to hold to a stop on the brakes, and acceleration got less smooth. Never any codes. Eventually failed while mechanic was driving it, with his laptop and gauges plugged in showing everything was fine. Just dropped drive and rolled to a stop.

 

[collywol]

Having only driven a Vario Tractor for a few days, (autocommand), I found slowing down from speed the single most unnatural thing and the only thing I didn’t like about the gearbox. No matter how I tried it always ended up with loads of revs piling on. What is the correct procedure?

Things like the above overspeeding down a hill also? Shouldn’t there be a engine/gearbox limiter to prevent this?

press the brake pedal maybe ?

 

[ColinV6]

press the brake pedal maybe ?

Using the brakes just seemed to make it rev loads too?

The only effective way of slowing down that didn’t result in a lot of revs was by starting to slow down waaaaaaaaay before you usually would.

 

[Lewis821]

Theres a farm close to me that runs 2 1050s. Whenever theres an issue the fitters know which one it will be. Its driven hard with the vario run at 5% so very little intervention, loading up the gearbox to pull harder ?, The tyres never reached 2000 hrs. The 2nd has only been seen when it needs servicing.
Mechanical empathy has alot to do with things

 

[deleted user 837354]

Range 2 for road work mainly...range 1 tops out at 25kph....forgetfulness the biggest cause

That is what I thought, just can't see how you can make such an elementary cock up.