5th gen 2 litre 4 stud rear brake discs

[vanzep]

just stumbled across a problem with 5th gen 4 stud rear brake discs
trying to help out a pal who asked for a bit of help

car in question is a 1998 ukdm 2 litre 5th gen

i always thought that all 4th gens and 5th gen 2 litre 4 stud would use the exact same rear brake discs - 260mm dia
so i gave him a set that i had stashed away for my 4th gen thinking they would do him fine for his 5th gen
turns out they dont fit and then he bought ones for his 5th gen that also dont fit

has anyone had this issue or can shed any light on what the problem or solution could be.
problem seems to be around the depth of the hub
any help would be much appreciated.

[ek9sid]

4g and 5g (2.0) run different discs. I've found this whilst working on a friends prelude. I can't remember how they were different, I just know thy were

I believe that all 5g 2.0 run the same discs. So it's strange that your friends don't fit, unless they were for a 4g and labelled up as 5g?

Purely speculating here but has it had and rear brake work done? Perhaps different calipers fitted from another model [EDIT: Thinking ATR rear caliper/carriers here] ?

[vanzep]

Thanks for the quick reply
yep even after owning a prelude for 20 years i still get things wrong i was sure 4g discs would fit
the 5g discs he bought have the correct part number according to lings but are too deep and rub against the backing plate

i hadnt thought about calipers maybe being the issue...car was owned previously by forum member Andy1000

[Scott560]

I always have a look at brakeparts.co.uk to try and work out any oddities, they list 3 different rear discs for entire 4th/5th gen lineup.

There are 6 entries overall, but all 3 of the 4th gen model types have the same disc.

All are 260mm
all are 64mm hub (one is listed at 64.1 but lets say 64).


https://brakeparts.co.uk/shop/Honda/Pre ... ms/BDS5434
This is listed for all 4th gens, 43.6mm height, 10mm thickness

https://brakeparts.co.uk/shop/Honda/Pre ... ms/BDS5725
this is listed for 5th gens 2litre, 42mm height, 9mm thickness

https://brakeparts.co.uk/shop/Honda/Pre ... ms/BDS5726
This is the 5 studder, no good, but 43mm height, 9mm thickness.

So according to those listings, the 4th gens are 1.6mm higher overall, including 1mm of extra beef on the discs. None of those listings list the internal 'hat' height so hard to make any sound conclusion other than separate part numbers must mean they are different and not interchangeable...

[Scott560]

the backing plates are easily bent when they get rusty - worth checking the removed discs against the purchased ones on the bench to see what is out of whack.

If they weren't OEM discs purchased, i wouldn't trust the OEM number on them, almost certainly reverse looked up and someone went 'ah close enough wack em on ebay'...

[ek9sid]

I'd echo what Scott has said. Get the new ones side by side with the old ones and see what's crackening.

If it's just the rubbing on the back plate then perhaps the calipers/carriers aren't the issue.

[vanzep]

wow 5th gens so complicated - 4th gen easy - imo
will pass on the info - im thinking the 42mm x 9mm thick ones might be the correct option

and yes backing plates can get a bit out of whack and easy to push them back a bit - sure ive done that on a 4th gen somewhere along the line

[vanzep]

Thanks for your help guys - much appreciated.
Looks like we have found the right part but out of stock.
https://brakeparts.co.uk/shop/Honda/Pre ... ms/BDS5725
this is listed for 5th gens 2litre, 42mm height, 9mm thickness

supplier is offering blueprinty ones ADH 24386

[ek9sid]

I'm not sure what the difference is between the ADH24386 and the BDS5725

They both appear to be of similar spec.