650HP-CTD

My '02 CTD 2500 w/128k miles started having a brake pedal that was slow to return when it was really cold out. I had recently replaced the front brake calipers while doing a brake job, so I thought I might not have gotten the brakes bled properly (only have a crappy vacuum bleeder). A local Dodge dealer pressure bled the brakes and supposedly did a full diagnostic check on the brakes only to charge me $180 and the brake pedal condition remained.



I checked the power steering fluid and it wasn't all that great looking, so I flushed the power steering fluid (slurping out the old, filling the reservoir back up, driving the truck around the block.....wash, rinse, repeat....using nearly a gallon of power steering fluid before I got it clean). Brake pedal issue didn't change but the power steering pump stopped squeeling on subzero mornings.

Now, 6 months later, on really cold mornings, the power steering pump gives a little squeel (not a belt squeel) and sounds kind of grindy for about 30 seconds. No power steering fluid leaks. Once it warms up the pump never makes a peep and it's fine on warmer days. Steering behavior is normal.

So, after a little research, I'm thinking my continued slow returning brake pedal could be the hydroboost unit. I might have a weak power steering pump as well but since the two are tied together, I'm thinking of replacing them at the same time along with the steering pump hoses.

Thoughts?

--Sk

SIXSLUG

You may have a vacuum leak.

650HP-CTD

I'm willing to entertain any ideas.....how would a vacuum leak effect the brakes when the truck uses a hyrdoboost brake booster? I'm not aware that vacuum plays any part in the system.

Junk Man

Are the rubber brake hoses all good? Try loosening the master cylinder & check for leaks by looking under the rubber seal. Are calipers all moving freely and wearing brake pads evenly? Is brake fluid clean?

Try some synthetic fluid in the steering pump. Mine was quieter after the change to Royal Purple.

nickg

here ya go,

650HP-CTD

**** Nick....you da man!

Thanks....I'll do a diag when the weather clears up.

From the looks of the condition/cause chart....my issues require either a hydroboost replacement, power steering pump replacement, or both.

650HP-CTD

Traced all the rubber hoses.....good condition, no cracks or leaks.

I'll try loosenig the m/c to check for leaks but I'm not loosing any brake fluid, so I'd not expect to find anything leaking.

Front calipers are relatively new and free floating last I checked (which was after this condition started).

Brake pads are wearing evenly in front and back . Rear calipers are original but were in good condition when we did the rear brakes just 1500 miles ago. Rear pads are currently evenly worn as were the old ones.

Brake fluid is clean....was just flushed with over a gallon of DOT 4 via pressure bleeder at dealership.

Good suggestion on changing the power steering fluid to synthetic. I changed out the 6sp manual transmission fluid to Redline and it drastically improved the shifting behavior.

Thanks for the suggestions Junk Man.

nickg

couple points:
when replacing booster no need to unhook Master Cyl brake lines, unbolt and move to the side, secure it so it cant be knocked over and kinking the lines. takes all of 15mins to remove
pay attention to the rod length, between MC and booster, you might have to swap in your orginal if they are different lengths.

I would replace the booster first, test drive, and if pump is still making noise issues/low pressure, then replace it. if you do have to replace it, pull it out with the Vacuum pump as an assy, and unhook the hi-pressure lines from the HB instead of unhooking the lines at the pump (no room down ther to swing a wrench, and good chance of stripping fittings) while pump/vacuum pump are out get a seal kit and replace the seal thats there, best to do now not later, kit is cheap from cummins (10-20$) comes with inst of how to replace seal

Junk Man

Nick, No fair posting the FSM.

I just did my pump seals & posted specs. This is for my 2000.

"I have some seals to do my power steering / vacuum pump & went to the bearing/seal house to see what they had so I can buy generic the next time.

Double lipped seal that goes around the shaft is a 28 x 38 x 7 ANBR (get the double lipped)

Large O ring is an " 039". He wasn't sure of material but Viton is fuel & oil impermeable and handles temps to 400*

Small O ring is 132. Also use Viton

Cummins gasket is pn 3929751 and goes between the pump & block.

There is also a braided steel line between the pump and block that is reusable unless yours is rusted & needs to be cut & replaced. I don't have that number but it will have to come from Cummins."

SIXSLUG

My bad on the vacuum leak, didn't read your sig.