macattack

Thanks Terry. Do I have to drain the oil?

Thanks . Ended up cutting off the ends of the both hoses and reconnecting with new clamps. Also replaced the 2 copper washers. So far so good. Again thanks for all the help

Thanks for the info. This pic was taken when there were no leaks. I will try to get a recent pic. Almost sure its oil leaking from the steel tube #10 on top of cooler. I think #11 the o ring in the diagram is my issue. Can that o ring and gasket be replaced without removing the cooler? Thanks again.

Developed a oil leak on my cooler. I am not familiar with a oil cooler and therefore any help is greatly appreciated. Does oil or coolant go thru the small tubes on the core? Also in the pic is that (about 1 in or 1.5 in) steel line above the cooler oil or coolant. I think that is where my leak is. I believe there is a couple of o rings and a gasket there. Again any help is greatly appreciated. Thanks

Would you happen to know what size the banjo fitting is and or size of the washers. Think I may try to pick up one fitting and washers before I tackle it. Thanks

Thanks. Gonna check this out on the weekend. I will Let you guys know how it goes. Thanks again great site

Thanks guys. Ģonna check that out. Hopefully I can get to it. So there may be o ring or just copper washers. Thanks again. Really appreciate the help.

Don't see a primer or lift pump Does that fitting with the tieback have a o ring? Would that be a banjo fitting? Only issue is that the fitting faces the engine and very little space in between. Hopefully I won't need to remove pump to gain access. Thanks

Found this pic online. I believe i may have leak at this fitting on the side of pump. I got this pic online and my pump seems to be leaking at the fitting pictured with the zip tie. What is this and can it be fixed without removing the pump? Thanks

Thanks. I will take a look. But I can't recall seeing it. Thanks again

Don't think i see a hand primer. Where would it be located? What does it look like? Thanks

Noticed for last while my 96 mr688 turns over quite a bit before starting. This only happens approximately once per month. When truck starts it operates fine, but every once in a while it spins over quite a bit before starting. Truck has air throttle. Anything I can look for. Gonna check for leaks and loose fittings. any o rings that I should be aware of on the pump that usually cause the issue I am having. There is a plastic line that goes between the pump and the engine. This line comes from the driver side of engine goes in-between the pump and engine and then connects to the rear top of pump I believe its called the android. Does it connect anywhere on pump before it goes to the android. Can't tell because it goes behind the pump between engine and pump Any points or tips would be helpful. Thanks

On my mr688 The brake light switch is located under the driver side floor board directly below brake pedal. Hope that helps

ok. i will get one made up. dont know if they have braided line though. good hyd line be ok? and is there a name for this hose in case i have to order one thanks again

got what looks like a oil leak developing on my fuel pump. there is a short approx 12 inch braided hose that comes off the side of the pump that looks like it needs replacing. my question is does it have to be a braided hose and is this a oil line? thanks

thanks guys.

my 96 mr688s seems to loose a bit of air when releasing the park brake. so i thought quick release valves, but on mine they look different. instead of one supply there are 2 supplys and 4 outs? per axle??? here are a couple of pics

thanks bud. the oem is #3MT237P7 gauge. the one i got is from allison, but the sending unit with the new gauge is a single wire the original sending unit is 2 wire. the allison gauge has your basic send and ign terminals. but there is 2 smaller bolts with an insulator between them one is labelled + and the other - . dont know what that is about. but your probably correct. thanks again

gonna replace my tran temp gauge and the original says neg ground stamped on the back. the replacement does not say anything. is there a way to find out if the gauge is neg or pos ground? thanks

thanks for the info. i am thinking i will splice a long wire from the sending unit (ground wire) and route it inside the cab and when the gauge decides to act up i could touch that wire to a ground source inside the cab just to see if the gauge stops acting up. think i will leave the sending unit hooked up as original but run a jumper from the ground wire to inside the cab. thanks again

this is on a 96 mack mr688s truck. trans temp sending unit has 2 wires going to it. one is the send is the other wire for ground? dam gauge wants to jump all over the place.

does mack have instrument panel voltage regulators? cant seem to find out

thanks j hancock. took me a while, but got it figured out. came close to replacing the trans. what a relief. so after a couple filters, relays, and a shitload of testing also a tcm ended up being that governor. took 30 mins to change.

happy days are here again!! yes got it figured out. my problem ended up being a worn trans governor. gear on governor looked fine but the inners were sloppy. replaced governor and put truck into reverse and she engaged every time. !!!!!

well still screwing around with this. anyways thinking possibly a switch issue of some sort. with engine off, if i shift into rev and back into neutral a couple times and then start the truck. it goes into reverse, but only once. seems something not switch, what do you think would the nss do this? could it also be an input speed sensor? any help would be great.