john deere 6630 poor brakes

[mf290]

The brakes on our 6630 seem poor. We recently bought it and it was well minded by the previous owner and given a full main dealer service at 2200hrs supposedly. There's only 2700 hrs on it so I'd doubt they're worn. The brakes seem very "dead" when there's nothing behind it. Only seems to brake ok when there's a well braked trailer behind it pulling it back, awful when there isnt a well braked one...
If I push the brakes hard to stop there's a squawky noise, even if there's nothing behind on occasion. Could it be from using the wrong standard oil? Air in the system?
TIA

 

[davidroberts30]

Brakes discs shot

 

[KB6930]

Fair chance the discs are glazed we've had one go that way in fact I think I've a 6930 needing attention just now but it's got 6000 hrs so probably due a set as a precaution. The sqwaking noise you say is it more like a hydraulic noise or a grinding/squwaking inside the backend noise? Sometimes the brakes on a JD can have a noise when pressing the pedal but it's just oil in the circuit somewhere

 

[mf290]

Fair chance the discs are glazed we've had one go that way in fact I think I've a 6930 needing attention just now but it's got 6000 hrs so probably due a set as a precaution. The sqwaking noise you say is it more like a hydraulic noise or a grinding/squwaking inside the backend noise? Sometimes the brakes on a JD can have a noise when pressing the pedal but it's just oil in the circuit somewhere

Think I know what you mean on the oil in circuit, used to happen on another 30 series I used to drive for a moment every now and then when you'd press the brakes.
I'd describe it as more a grinding squawking noise coming from the backend. Loudish when I had to stop with a trailer with poorly adjusted brakes the other day... (far from ideal I know)
What would cause the brakes to glaze? Would that mean replacing?

 

[james ds]

Replace them before they put fileings through the back end , if that happens your in big trouble .

 

[davidroberts30]

Glazin

Think I know what you mean on the oil in circuit, used to happen on another 30 series I used to drive for a moment every now and then when you'd press the brakes.
I'd describe it as more a grinding squawking noise coming from the backend. Loudish when I had to stop with a trailer with poorly adjusted brakes the other day... (far from ideal I know)
What would cause the brakes to glaze? Would that mean replacing?

Glazing caused by heat
Prolonged braking and un or poor braked trailers
Whip the trumpets off and change discs before bits of them float round the system

 

[Sharpy]

I had a similar problem with the brakes on my 6620. Took discs out, looked fine, took them to my local John Deere dealer, compared them with new ones. No difference! Put new ones in anyway. Still squawked. Was on John Deere oil. Changed oil and filters again. No better. Went to change the oil and filters again and was out of the John Deere oil. Put GB lubricants Unitrans in. No squawk. That was 5 years and 2000 hrs ish ago. Still no squawk.
I would try the same if your discs look ok.

 

[michael N123]

Can you adjust them on a jd

 

[davidroberts30]

@Phil P

 

[Phil P]

Thanks @davidroberts30, chances are they are just a bit glazed but for what it cost to put new ones in it's not worth the risk of leaving them (gets expensive quickly if they brake up).
A good tech will do the job in 6-8 hours possibly less if the trumpets come off handy.
There's no adjustment on jd brakes, just remember to press the pistons back in when your replacing the discs.
To be honest though I have a 6630 with less than 600h and the brakes are no where near as good as my 6520 with 3000h. Neither make any noise when braking though.

This is a 6520 but no real difference.

 

[mf290]

Thanks @davidroberts30, chances are they are just a bit glazed but for what it cost to put new ones in it's not worth the risk of leaving them (gets expensive quickly if they brake up).
A good tech will do the job in 6-8 hours possibly less if the trumpets come off handy.
There's no adjustment on jd brakes, just remember to press the pistons back in when your replacing the discs.
To be honest though I have a 6630 with less than 600h and the brakes are no where near as good as my 6520 with 3000h. Neither make any noise when braking though.

This is a 6520 but no real difference.
View attachment 593108

Sounds like a job for the mechanic, we're more vice grips and lump hammer men... When you say press the pistons back in would that be obvious to a general mechanic or is it something specific to jds that he'd need to be warned about?

Thanks lads, appreciate the replies I'd be nervous hearing stories about shot brakes and filings

 

[james ds]

Sounds like a job for the mechanic, we're more vice grips and lump hammer men... When you say press the pistons back in would that be obvious to a general mechanic or is it something specific to jds that he'd need to be warned about?

Thanks lads, appreciate the replies I'd be nervous hearing stories about shot brakes and filings

I know of JDs that were traded in after their brakes went , fileings went through the system , hard to get it right after.

 

[KB6930]

When you do get it done if they have started to come to bits get the pto housing taken off and cleaned out as well there's a ledge between it and the diff housing that sh!t can lie in behind till the pto is engaged and stir it up again. It'll cost a bit more at the time but save a lot in the long run.

 

[Phil P]

Sounds like a job for the mechanic, we're more vice grips and lump hammer men... When you say press the pistons back in would that be obvious to a general mechanic or is it something specific to jds that he'd need to be warned about?

Thanks lads, appreciate the replies I'd be nervous hearing stories about shot brakes and filings

It's not an overly complicated job, the trumpet housings can be tight to get off sometimes but it's just nuts and bolts apart from that.
The piston sits in the diff housing and presses against the friction disc, it has three retractors behind it that pull the piston away from the disc slightly when the brakes aren't applied.
They also adjust the piston up as the friction plate wears so need to be pressed back when new discs are installed.
I just bolt a plate across then push it back with two heal bars.
This is what they look like if they get left to long.

Not that I'm trying to freak you out or anything, but if the filter light comes on park it up and pull it to bits

 

[davidroberts30]

Messy

 

[Robt]

I know of JDs that were traded in after their brakes went , fileings went through the system , hard to get it right after.

I know a gullible Irish man too... just saying....

 

[james ds]

I know a gullible Irish man too... just saying....

Seeing is believing . And don't worry I've seen plenty .

 

[ollie989898]

Yep, flashing lights and filter light. Make sure your trailer brakes are all tip-top, always or it's gonna get expensive.

Out of interest, does the JD autopowr gearbox have it's own oil supply or it is also fed from the backend with the iron filings in?

 

[Pheasant Surprise]

Out of interest, does the JD autopowr gearbox have it's own oil supply or it is also fed from the backend with the iron filings in?

It’s common gearbox and hydraulic oil in the JDs. Some other makes separate the two, but the wet brakes stil run in the same oil as the transmission.

In the separate gearbox / hydraulic types, there is only protection to the trans from hydraulic contamination, rather than from brake discs/friction material breaking up.

 

[james ds]

It’s common gearbox and hydraulic oil in the JDs. Some other makes separate the two, but the wet brakes stil run in the same oil as the transmission.

In the separate gearbox / hydraulic types, there is only protection to the trans from hydraulic contamination, rather than from brake discs/friction material breaking up.

I know of a 6620 which would be owned by a rough enough operator , money would be tight , he didn't do the brakes in time , bits went through the system , did the brakes and cleaned it out, the ram seals in the loader started giving trouble after , power steering ram as well started leaking , had to trade it in as it wouldn't stay going without giving trouble.