e9500v8

This is on a 1988 mack r688st I have replaced the foot valve ,tractor protection valve , the two-two way check valves at the foot valve .This thing is driving me nuts if I push brake pedal lights will stay on for a long time till air leaks off .I am an ASE certified diesel mech I have worked on macks for 15 years and this one is killin me . Aside of replacing all the valves on the truck I am at a loss any help would be great.

Try IB diesel in pennsylvania . They have done a few of them for guys I know and do an excellent job .Or try Michigan turbo I have personally had very good luck with them and they are very knowlegeable. Good luck when you get a good one let me know cause I would like to buy one myself!!

evening gentlemen,

I have an '88 r688st with an E6 350 econodyne and a 12 speed mack tranny. Its the one with a direct/high/neutral/reverse all air shifted and also has a low/direct air shift on the dash for lo lo. What tranny is this, what oil do i use, and how much? also, i believe i have mack rears as well, but how can i find what model axles i have and what ratio they are? thanks

In low gear your ratio is 23.08 to 1 and the over drive in the 12 speed is .78 pretty fast!!

evening gentlemen,

I have an '88 r688st with an E6 350 econodyne and a 12 speed mack tranny. Its the one with a direct/high/neutral/reverse all air shifted and also has a low/direct air shift on the dash for lo lo. What tranny is this, what oil do i use, and how much? also, i believe i have mack rears as well, but how can i find what model axles i have and what ratio they are? thanks

On your rearend on top right on the sloped part below the breather there is a flat place clean it all off the gear ratio will be there probly 4.17 or 4.42 or 4.64 rarely could be 5.13 .For the transmission there is a flat place on one side or the other that has the numbers stamped in it also. I have the identical truck but i replace the 12 speed mack with a 13 speed fuller !! I just use gear oil the check plug is on the right side rear it is usually a square headed plug ,they hold about 4 or 5 gallon.You fill the oil up till it comes out the check plug!!

When was the last E9 put in a CL?

pretty sure it was 1999

Where does the tachometer connect to the engine on an 86 R688 ST? Engine was put in before I bought it and previous owner said it never worked after that, its a 300,,,thanks,,,Randy

right under the injection pump !!