Mack CF Posted October 20, 2010 Share Posted October 20, 2010 I broke the truck. Normaly every day im home i start the truck up because its outside til we find a place for it. Today, the steering wheel felt lose, like it was easier to move. I started the truck up and turned the wheel a little and it went BOOM. Then i lost steering. Ok fantastic, so i looked underneath and saw that the arm that goes to the output gear from the power steering cylander underneath came off. So pretty sure i found the problem i tried putting it back on. There are two screws that i had to undo with plyers and loosen them up. But still no go. I was able to get it on a little, but again the wheels turned a bit and boom again it came off. I dont know if i just have to match up the arm with the gears or if something is damaged. Attached is a few pictures of what im talking about. Power steering still works fine, just lost the arm that connects it to the rod that goes to the wheels. First picture is an outside shot of the mechanism. Second is looking up into it where the arm popped off of the gear. The thing protruding at the top is a screw, there were two of these that i had to loosen with plyers to help troubleshoot. How can i fix this? Im hoping its something as easy as aligning the gears and popping it back on the shaft? Quote Link to comment https://www.bigmacktrucks.com/topic/16218-loss-of-steering/ Share on other sites More sharing options...
Mack CF Posted October 22, 2010 Author Share Posted October 22, 2010 No one? I tried pushing it back on with a friend turning the steering wheel and trying to get the gears to line up. Can anyone help? Quote Link to comment https://www.bigmacktrucks.com/topic/16218-loss-of-steering/#findComment-65704 Share on other sites More sharing options...
convoyduel Posted October 23, 2010 Share Posted October 23, 2010 You need to dismount the power steering gearbox and look at the shaft and arm in detail. That is not something that is "normal" and without diagnosing the exact cause, you risk literally killing yourself or someone else if you try driving the truck without fixing it 100% properly. I'm sure everyone knows this already, but steering repairs are NEVER something that should be shortcut or done half-ass. That gearbox is very heavy and its location makes it extremely awkward to handle. I suggest using a rolling 2 ton floor jack to support and lower the gearbox if possible (even if you're outside and laying in the dirt or gravel). Quote Link to comment https://www.bigmacktrucks.com/topic/16218-loss-of-steering/#findComment-65708 Share on other sites More sharing options...
rhasler Posted October 23, 2010 Share Posted October 23, 2010 No one? I tried pushing it back on with a friend turning the steering wheel and trying to get the gears to line up. Can anyone help?It looks like the pitman arm came off of the sector shaft on your steering gear. It appears to be an R.H. Sheppard gear, so check their website for specifics on reinstalling. I would imgine that you will need to remove the gear from the frame rail and locate the timing marks on the gear and on the pitman arm in order to get everything back in time. http://www.rhsheppard.com/home.htm Quote "Mebbe I'm too ugly and stupid to give up!" Link to comment https://www.bigmacktrucks.com/topic/16218-loss-of-steering/#findComment-65709 Share on other sites More sharing options...
theakerstwo Posted October 23, 2010 Share Posted October 23, 2010 I second what all has said and if your not a good truck mechanic dont try messing with it.So many trucks have been put in the salvage yard over this kind of thing. when you stop and think about it the whole thing is a blessing that it happened the way it did. The good Lord has been helping you out some there.The shaft and arm is what i would say worn out because the bolt that holds it on dont come off for no reason with out the spline being worn. Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/16218-loss-of-steering/#findComment-65711 Share on other sites More sharing options...
rhasler Posted October 23, 2010 Share Posted October 23, 2010 ...and if your not a good truck mechanic dont try messing with it.So many trucks have been put in the salvage yard over this kind of thing. when you stop and think about it the whole thing is a blessing that it happened the way it did. The good Lord has been helping you out some there.The shaft and arm is what i would say worn out because the bolt that holds it on dont come off for no reason with out the spline being worn.Once saw a truck drive across the state after having an M100 steering gear "rebuilt" someplace. He was complaining that the truck wouldn't steer one way. When they assmebled the gear they didn't time the parts correctly, at steer ahead the pitman arm was toggled backwards about 150 deg. If the splines are damaged don't try to scrape by, it's not worth the liability involved. Remanufactured steering gears are fairly affordable and should be readily available through Straight Line (http://www.straightlinesteering.com/) or Mascot Truck Parts (http://www.arvinmeritor.com/products/aftermarket/northamerica/mascot/default.aspx) Quote "Mebbe I'm too ugly and stupid to give up!" Link to comment https://www.bigmacktrucks.com/topic/16218-loss-of-steering/#findComment-65714 Share on other sites More sharing options...
MACKS Posted October 23, 2010 Share Posted October 23, 2010 First thing to do is disconnect the pitman arm from the drag link then check the splines on both the pitman arm and the gear shaft,sounds like it's been lose for some time and the splines are more than likely shot at least on the pitman arm if so it will never tighten up properly,if you reuse the pitman arm or buy a new one install it before connecting it to the drag link look for the set screw marks on the gear shaft and you should be able to get it exactly where it was,after it's on check for equal travel in both directions make sure the set screws are tight,thats what holds it on.Good Luck Quote Link to comment https://www.bigmacktrucks.com/topic/16218-loss-of-steering/#findComment-65715 Share on other sites More sharing options...
theakerstwo Posted October 23, 2010 Share Posted October 23, 2010 Once saw a truck drive across the state after having an M100 steering gear "rebuilt" someplace. He was complaining that the truck wouldn't steer one way. When they assmebled the gear they didn't time the parts correctly, at steer ahead the pitman arm was toggled backwards about 150 deg. If the splines are damaged don't try to scrape by, it's not worth the liability involved. Remanufactured steering gears are fairly affordable and should be readily available through Straight Line (http://www.straightlinesteering.com/) or Mascot Truck Parts (http://www.arvinmeritor.com/products/aftermarket/northamerica/mascot/default.aspx)A rebuilder in Dallis a few moths ago priced rebuilding a box of mine or exchangine one for a inside frame rail mack for 440.00. But two weeks ago i had to have one on my superliner and got one her over night from our spring shop and it was about 675.00 but its worth it to not worry about a half wore out part that can kill you and some ones little buddy child out there.That would kill me to have to live after killing a small child that was riding around with his mommy just having fun for the day. Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/16218-loss-of-steering/#findComment-65716 Share on other sites More sharing options...
Mack CF Posted October 23, 2010 Author Share Posted October 23, 2010 Well, ive been having bad shaking and wobble at 30 MPH to 50, so im guessing that might have helped loosen it up. Luckily i live close enough to watts mack, so im seeing about a mechanic coming out to my house to look at it and see what they think. Im definatly NOT driving it until i get someone to approve it IF i get it back on. Thanks for the help guys. Quote Link to comment https://www.bigmacktrucks.com/topic/16218-loss-of-steering/#findComment-65719 Share on other sites More sharing options...
MACKS Posted October 23, 2010 Share Posted October 23, 2010 Well, ive been having bad shaking and wobble at 30 MPH to 50, so im guessing that might have helped loosen it up. Luckily i live close enough to watts mack, so im seeing about a mechanic coming out to my house to look at it and see what they think. Im definatly NOT driving it until i get someone to approve it IF i get it back on. Thanks for the help guys.I'm betting that was the reason for the shaking and the wobble and if it's been loose for an extended time it's toast. Quote Link to comment https://www.bigmacktrucks.com/topic/16218-loss-of-steering/#findComment-65720 Share on other sites More sharing options...
Rob Posted October 23, 2010 Share Posted October 23, 2010 I'm betting that was the reason for the shaking and the wobble and if it's been loose for an extended time it's toast.Those "M" series boxes shake the shit out of the truck when they run low on fluid. Both of my midliners had them and if the steering gear leaks, the oscillations that are setup in the steering gear are hazardous at best. This doesn't take hitting a bump in the road either. Driving on smooth road one of mine would start to shaking badly about 60mph. A replacement with a rebuilt unit and the problem was gone forever.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment https://www.bigmacktrucks.com/topic/16218-loss-of-steering/#findComment-65721 Share on other sites More sharing options...
Mack CF Posted October 24, 2010 Author Share Posted October 24, 2010 Thanks guys! At first i thought it was the bias tires going. But after thinking for a while, if it were the tires the truck would shake going at ANY speed correct? What was odd was the truck only did it between 40 and 50 MPH, the front tires were at 48 psi (tire says should be inflated to 100 PSI) So i cranked them up to 80 PSI to give them a slow break in with the increased pressure. Wobbling stopped for a mile or two, then started doing it at 30-50 MPH, only worse. Quote Link to comment https://www.bigmacktrucks.com/topic/16218-loss-of-steering/#findComment-65751 Share on other sites More sharing options...
HK Trucking Posted October 24, 2010 Share Posted October 24, 2010 You are very very lucky that tha pitman arm didn't come off the shaft during one of those "shaking" episodes at 30 - 50 MPH, or quite possibly you wouldn't be here to tell us about it.I agree, the sector shaft & pitman arm are likely junk after being run loose like that. Quote "If You Can't Shift It Smoothly, You Shouldn't Be Driving It" Link to comment https://www.bigmacktrucks.com/topic/16218-loss-of-steering/#findComment-65772 Share on other sites More sharing options...
fjh Posted October 24, 2010 Share Posted October 24, 2010 You are very very lucky that tha pitman arm didn't come off the shaft during one of those "shaking" episodes at 30 - 50 MPH, or quite possibly you wouldn't be here to tell us about it.I agree, the sector shaft & pitman arm are likely junk after being run loose like that.I second that one Herb! I also beleive that is the cause of your origanal complaint! Quote Link to comment https://www.bigmacktrucks.com/topic/16218-loss-of-steering/#findComment-65775 Share on other sites More sharing options...
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