Brake imbalance - how to rectify

Yorky1

My Nissan Primastar (same as Renault Traffic) van passed the Irish MOT test recently but I noticed on the Pass Statement the Service brake axle 2 imbalance is 28.67% when the maximum is 30% so it almost failed on this part of the test.

The brake effort is as follows:

Service Brake axle 2: Nearside 213KGF, Offside 298KGF

Service brake performance: 66.61%
Parking brake performance: 21.97%

Having looked at previous Pass Statements, the imbalance has increased with each DoE test.

The Nearside KGF has decreased while the offside KGF has increased - last year it was 236 and 269 respectively.

Would this suggest the rear Nearside calliper needs replacing? If not, what else could be the problem?

Thanks in advance for any advice / tips - going on a long journey soon and afraid of the calliper seizing!

marlot

It could just need stripping and cleaning. especially the slider pins, assuming your calipers have them (most do)

Yorky1

Would the lack of pressure on the nearside cause the extra pressure on the offside (as listed above)?

forgotmyname

If one side is sticking it wont be applying full pressure where the opposite side will be at its full value.

Handbrake 298 and 213, When fixed you should have both sides at 298. What you probably have is the cable on one side sticking and its pulling the otherside further hence the higher figure.

Full strip and clean and check for sticking calipers or cables and possible new shoes or pads.

AdrianC

Yorky1 wrote: »

Would the lack of pressure on the nearside cause the extra pressure on the offside (as listed above)?

There isn't extra pressure on the offside. There's less pressure on the nearside.

arcon5

No there wouldn't be extra pressure on r/o/s more likely extra f/o/s.

pull the caliper off, pop the piston out, inspect for any debris or rust. Clean up any outside side of the seal. Get some stiltons and work the lever, penetrating fluid at it from all angles.
Brake cleaner to clean it all up. Piston back in (easy peasy if you keep it true).
Back on car and bled up.

This is usually enough to free everything off until next year.

forgotmyname

Cheese fixes brake problems? never tried that.

arcon5

forgotmyname wrote: »

Cheese fixes brake problems? never tried that.

Try it then and post up the results;)

EdGasket

arcon5 wrote: »

Get some stiltons and work the lever, penetrating fluid at it from all angles.

...and if your brakes squeak, just look for the mice after your cheese.