help required mk1 front brakes

[Preen59]

two 15mm? bolts

P.S. Best, most detailed reply will receive free naked pics of my mum....

Err, 16mm, no such thing as a 15mm bolt. Sorry i had to say it. This no common sense 'engineer' out at work asked me and another guy to use a 15mm bolt to hold up this tiny RHS beam once. It's a bit of an in joke at work.

Not saying you have no common sense though, because you've got on here and asked people admitting you know very little instead of being arrogant and going balls and all into it and wrecking stuff. So thumbs up!

What's your mum look like?

[Peter Jones]

I just had a look at my cars. They are both originally GLDS and both had 10mm discs on them when I got them. They each had the different styles of callipers though. I fitted DB-105 pads to both of them and have been stopping happily ever since.

I seem to remember returning a set of pads once because they were too thick, these could have been the DB-128s I suppose, which kind of makes me wonder what's going on here.

One car has since been upgraded to GTI vented rotors which use DB-401 pads.

The other has new 10mm discs and is definitely running DB-105 pads.

I had a look at the Bendix catalog and a few others and got more confused.

They claim the DB-128 is the one for a diesel and is 18mm thick.
Likewise they say the DB-105 is for petrol and is 14.8mm thick.

In any case the DB-105 could be considered as a partially worn down DB-128 because they're they same shape just thinner.



When I fittted the brand new 10mm discs, the DB-105s were quite a snug fit, I don't think I could have gotten another 6.4mm of pad in there. I made sure the piston was fully pressed back beforehand too.

Pete

[ontarv]

thats a normal most people don't know
that the bolt size goes by the thread eg: m10 bolt
a 10 mm thread with a 15 mm hex head thus the prob
small things we all learnt at some point in time

[Peter Jones]

Err, 16mm, no such thing as a 15mm bolt. Sorry i had to say it. This no common sense 'engineer' out at work asked me and another guy to use a 15mm bolt to hold up this tiny RHS beam once. It's a bit of an in joke at work.

Not saying you have no common sense though, because you've got on here and asked people admitting you know very little instead of being arrogant and going balls and all into it and wrecking stuff. So thumbs up!

What's your mum look like?

Both wrong I'm afraid. The head of the bolt is 15mm The bolt itself is an M10.

Pete

[gldgti]

PM sent.

DB 105 goes with 10mm discs on a GLD (Diesel)
DB 128 goes with 12mm discs on a GLS (Petrol)

DB105 and DB128 are the same shape but the DB105 is thicker.

so

DB128 will work on a 10mm disc.

I think you can use either combination of disc/pad as I'm pretty sure the GLD and GLS calpiers are the same. Can someone please confirm this?

Pete

caliper offset is different, as disk offset is different.

[gldgti]

I just had a look at my cars. They are both originally GLDS and both had 10mm discs on them when I got them. They each had the different styles of callipers though. I fitted DB-105 pads to both of them and have been stopping happily ever since.

I seem to remember returning a set of pads once because they were too thick, these could have been the DB-128s I suppose, which kind of makes me wonder what's going on here.

One car has since been upgraded to GTI vented rotors which use DB-401 pads.

The other has new 10mm discs and is definitely running DB-105 pads.

I had a look at the Bendix catalog and a few others and got more confused.

They claim the DB-128 is the one for a diesel and is 18mm thick.
Likewise they say the DB-105 is for petrol and is 14.8mm thick.

In any case the DB-105 could be considered as a partially worn down DB-128 because they're they same shape just thinner.



When I fittted the brand new 10mm discs, the DB-105s were quite a snug fit, I don't think I could have gotten another 6.4mm of pad in there. I made sure the piston was fully pressed back beforehand too.

Pete

the thick pads are (i think) for machined down disks (9mm). i also had these once, and the bench grinder made them fit for me

[gtimk5]

Take it from someone in the trade.
128s are for petol, 105s are for deisel. The part number for deisel discs is
811 615 301 or 823 615 301. Definate!!
Andrew

[Peter Jones]

Thanks Andrew I was sure the DB-105s were for Diesels!!

Pete

[gtimk5]

No problems Pete! The 105s are 15m/m thick and the 128s are 18.5 m/m thick
You cannot put 128s in the deisel carriers. The difference in the discs themselves is the offset. Not interchangable without changing the caliper to suit.
Cheers, Andrew

[Peter Jones]

Ahh , but which is better?

What was the thinking at the time? There can't have been much of a price difference.

Do you think that they were aiming to keep the discs in their ideal operating temperature range or were thay just trying to save a dollar?

Given that a 12mm disc can be machined down to 10mm and a 10mm disc can be machined down to 8 what are the implications?

As they're the same diameter and swept area the braking effect should be the same so it must have something to do with heat dissapation and generation.

Was the theory that the petrol cars went harder and that they'd heat their brakes up more?

Did the diesels go so slow their brakes never got up to temp?

The diesels had slightly heavier motors and different front springs, does this come into the equation?


Arggh so many questions


Pete