M923 Bob

[bigboy44]

Have you got the truck to the scales yet? I am still interested in the fuel MPG also. Thanks

 

[Dead Reckoning]

Great Job! I hope mine turns out as well.

 

[hawaii5ton]

I haven't been driving the truck. I currently have it torn apart to put a fuller 13 speed in it. Still not sure of weight or fuel mileage but the standard trans will undoubtedly change that also. I am going to post some more pics when i'm done.

 

[MO MV man]

Excellent thread! GREAT JOB! I JUST won an M931A2 off GL and plan to bob it just like I did my deuce.

 

[Rusty Nut]

Thanks so much for sharing the details and pics. Sweet ride. Dang you work fast- must be that good coffee.

Now, where did I leave that hacksaw.....

 

[spook]

Hawaii, your truck looks great, and I am using it as the inspiration for the pending bob of my recently acquired 925A2. Your attention to proportion is admirable, and you did make it look too easy so I'm breaking out the torches soon....I think.


I have been diligently measuring mine and photoshopping it with different length beds and side-rail configurations, and I am running into a discrepancy in my calcs vs my photoshopped results. You stated that your bed is 11'-9", but it looks like you did take out only one section of the bed side rails. Is the 11'-9" a typo maybe that should be 10"-9"? I can't get 11'-9" to look right (like your bed!) in my altered pics. Or, did your bed start out at 15' long?


Also, I have a question regarding turn radius that I'm hoping you or the other guys can help with. I know you are happy with your radius as it is definitely shorter by removing the rear-rear axle and leaving the front-rear in its original location. As my truck is a 925, I don't think my sense of proportion gets satisfied by leaving the proposed single rear axle so close to the front axle .....the truck will just be too "front heavy" (aesthetics because of the winch, not tonnage). I think it looks best, for mine, when I put the single axle exactly centered between the two original rears locations. This puts the tire directly under the center "bay" of the bed, with one "bay" removed from the length, because I plan to leave the spare/davit/muffler in the original configuration.


This leads me to my question: will the turn radius be any different with one centered axle than it is now with the tandems? My theory is that it won't, because it seems that in a turn the front-rear axle scrubs a bit the opposite way of the rear-rear......both moving opposite ways from each other around a pivot point centered between the axle-lines. I hope I'm wrong because I would like a shorter turn radius, but I will appreciate any feedback from those more learned than I.


Thank you for your help!

 

[Naterik]

Spook, I'm currently bobbing my M925A2 and my plans are the exact same as yours I thought that wheelbase was too short for a 925 in the front rear stock location with almost 3' of winch hanging out front. Also I'm not a big fan of bed overhang or the bumperettes in the rear. I've decided to locate my axle about 8" ahead of the old center line of the tandems. With a 10' 6" bed that will retain the proportions of a regular cab long bed pickup (about 2' more bed ahead of the axle than behind) I think it would be fine if not wanting to keep the spare tire carrier and stack in the stock locations, but I prefer to keep them. Even if the single axle was mounted directly centered where the old ones were I think it will still turn shorter because you won't have the axle scrub.

Currently I have the frame rough cut in the rear close to length, have removed, refabricated and reinstalled the old trunion crossmember to the size of a standard frame crossmember and closer to the rear so it would not interfere with the axle in its new location. I still need to drill holes and mount the spring hangers and rear hitch, replumb the air lines and cut the bed down. It has been a fun project so far except for the crossmember it was challenging and irritating, but necessary. I plan on doing a build thread when it is complete, which I hope to be within a month. It's just hard to get much done only having one day off a week on top of the weather we've had this winter.

There are a lot of knowledgeable, and helpful people on this forum. I have learned a tremendous amount of things about these trucks just using the search function it can be a life saver. Good luck with your plans and remember to take lots of pictures.

 

[hawaii5ton]

My bed is 11'9" if you look closely I moved the bed forward, put drive axle in front tandem axle position, and kept the stock overhang. I didn't just remove one section of bedside, I split the difference across the center.

 

[hawaii5ton]

Here is a pic of where I took the cut

 

[hawaii5ton]

Without the normal tire scrub my truck turns a lot sharper. I can do a full 180 in a cul de sec without backing up. That is almost impossible with my crewcab pick-up.

 

[tobyS]

Hey guys, I would like your opinion on rear suspension for a bob. I'm talkin 4 link.

Please take a look at the parts you have taken off, starting with the frame trunion that dogbones attach to and it holds the spring. Notice there are 3 links that move just as one would want a four link to. See how the bottom (dogbone) link is attached?....now envision two links on top and outside the frame, where the spring is/was. See the holes already in the frame trunion for that top link to work? There are holes for four, not only the three that are used and they are in the correct location (or would not work with three).

The setup would require a panhard or watts link and air bag, but I'm just asking for you to comment on using these parts for the front four links since you have recently removed them. They sure look promising, since they perform the function now.

 

[Tinydragon2001]

Is there anything in particular I need to know about mounting the rear axle to the front axles.