M37 Front Cross-member Mods

[maineSS]

I'm wondering if the sideways jump is suspension or steering- would it happen with crossover steering? When I hit a bump at speed, it always seems to want to jump to the driver's side. With frame side steering, a hit on the axle is transmitted directly to the steering box, and pivoting the spring at the rear insures you take the hit before the axle moves up. It would be interesting to see if shackle reversal or crossover steering would be more effective at stopping the hop, or if it would be a 50/50 split. Are you intending to do shackle reversal along with cross steering? If so, perhaps you could do one first, get some bump experience, then try the other. If you do rockcrawling, a shackle reversal would be helpful if you're sliding the springs over boulders. There's a pic in Bruce's thread at post 533 on page 36 (http://www.powerwagonadvertiser.com/...t=5521&page=36 ) for those who want to see how it looks. Your frame mods sound like they'll keep you busy for awhile!

[lebowski]

I spoke with a long time local hot rod fabricator today (22yrs in the hobby and with a very good reputation), and showed him a pic of the frame and crossmember. He said it's not uncommon to move/modify crossmembers for hotrods and it usually goes without problems. If your not using it as a motor mount point it would be not too difficult to put a straighter crossmember in there to accomodate the crossover steering he thought. He suggested contact your local hotrodders and the more experienced fellows with builds would most likely have some good suggestions. He was of the opinion that with some thought, a crossmember mod was very do-able and would be fine.

[Bruce in BC]

I got over a hundred frames under my belt

I have no rational explanation as to why I did not build one for the carryall . The only problems I see with using a flat cross member are .
(1) rad clearance - unless the radiator goes in front of the cross member the rad had to be smaller than stock .
(2) Lower rad hose interference with the cross member . It might be necessary to tube or relieve the cross member to allow passage of the lower hose.
It may be possible to eliminate the cross member or minimize the cross member. If you have a cross member added under your engine and motor mounts , If you have a cross member at the front of the springs . All you need then is to support the rad and remove any steering box flex .

[MasterYota]

From my quick looks under the frame, the rad attaches to the front of the crossmember, and there are no issues with lower rad hose or tank clearance. I've got the truck in the shop now so I can take better measurements as I take the sheetmetal off and get the engine out and trans out. My estimation is that I can either shorten the Crossmember as Bruce has done, or build a flat unit (as others have suggested).

I don't see much reason for such a large crossmember other than to either protect the front-bottom of the engine, or to ensure enough clearance for the engine crank and components. While it is the primary front crossmember, I belive I can adapt something to work as well with less space being taken up.

I prefer the crossover steering and shackle reversal (shackle at rear of the spring) as it seems to handle and ride better than the other setups. Push-pull steering has such short linkages and sharp operating angles that they inherently suffer from bump-steer regardless of where the shackle is.

My M37 will be used for a little bit of everything, and be capable of doing most things onroad and off fairly well (at least, thats the plan!). The terrain up here in central BC has a healthy mixture of everything - desert, rocks, mud, trails, gravel roads, tight'n'twisty, and whatever else you can think of. I'm leaning towards reasonable articulation, good road manners, and something that I enjoy driving that is both practical and predictable. Its a tall order, but I have the time to do it right.

[lebowski]

MY, just probing further on your build. Besideds the front D60 what else are you envisioning?

[MasterYota]

MY, just probing further on your build. Besideds the front D60 what else are you envisioning?

Well, I live in hilly country so an engine swap is also in the works. My power plant of choice right now is a 69 428CJ - its sitting on shop floor patiently waiting to go between the rails. Behind that is an NP435 (Ford Version) with a single speed Dana 21 tcase hanging off it. My plan is to use the D21 to operate my PTO winch, as the 435 pto port is on the wrong side. Behind that the stock NP200 tcase will stay put, but be converted over to a centered rear output to mate up to the GM 10.5 Corporate 14 bolt rear axle. I'm planning on using the original rear leaf springs, but I may incorporate a shackle flip in the rear to gain some height if the front end sits higher. I've already sourced a disc brake conversion for the rear, and a new set of 4.56 gears for better road speed.

Some hanging pedals and a tilt steering coloum should round out most of the interior mods. I've some newer seats I may install as well, but I'll need to see how they fit before I do anything permanent. Naturaly a conversion to a 12volt electrical system will follow the engine swap. Locking diffs at both ends, and tires around 38-42" tall should round out the package nicely.

I liked the way that Will Watsons truck looks and performs from the pictures so I'm going to copy his setup but with my own spin on it...

It seems like alot of work, but I'll break it down into smaller projects so that it dosen't get overwhelming. Or at least thats the plan!

[lebowski]

MasterYota,
I wonder if you could run military Hummer rims on SRW D60 front without using spacers with these steering arms?

http://www.northwestfab.com/dana60steeringarm.html

[MasterYota]

MasterYota,
I wonder if you could run military Hummer rims on SRW D60 front without using spacers with these steering arms?

http://www.northwestfab.com/dana60steeringarm.html

I had the same thoughts, but I orderd my Steering arms from Great Lakes Offroad - http://www.greatlakeoffroad.com/ . My thoughts of using the spacers where more to match the original track width than anything else. I may need the spacers now as I recent purchase the tires for the truck - they are bigger than what I was intending, but the price was too good to pass up. At 18.5" wide I might need the spacers just to maintain some sembalance of a turning radius.

The buildup of the truck with pictures can be found here:

http://www.g741.org/PHPBB/viewtopic.php?t=2420