Alright my dudes, since I've been doing a lot of measuring on my truck for modifying the frame and maybe building custom suspension for it I've noticed odd things about the truck the major one being that the drivers side fender seems to be a full inch wider than the passenger fender. I'm just wondering what tolerances are on these 30s and 40s cars and trucks, like its built in the 1940s so I'm sure the build quality isn't quite what it is now. My truck had been hit pretty hard on the drivers side (why the fender doesn't match) but I'm fairly certain that the frame isn't tweaked, or at least doesn't seem it when i measure it so I'm just questioning if that sort of thing is normal? thanks in advance! Sent from my SAMSUNG-SGH-I337Z using The H.A.M.B. mobile app
wider probably means the truck ran into something that pushed the fender back and out. Pull on the front of the fender and see if it gets 'narrower'
Is it possible the fender was replaced after a crash with a larger 1 1/2 ton truck fender. Some times the bigger trucks had the same cab with larger fenders to clear big tires.
Metal parts being produced on a die like a fender will be very consistent from one to the other even back then. In theory. The left and right sides should be mirror images unless the differences were intentional. Where I think you see the differences is in today's much tighter quality controls when it comes to assembly tolerances and manufacturing tolerances for other non die produced parts. Having said that, yesterday I was commenting on the horrendous gap on the rear cargo compartment lid on a Dodge Ram parked beside me. What gives? That is just very bad design/engineering. Yikes.
Well, since the body lines don't line up either on that Dodge bed storage container., I would suspect either the lid, or the latch is out of adjustment, or something inside is causing an issue. Those storage boxes have been an option for a couple of years already, one can not discount how much abuse it may have already seen. Then again, it could have been that crappy of a fit when new. Gene
back in my day at AMC it depended on what day of the week it was, or if we were heading into a strike. Spec was way looser on Mondays and Fridays. Total disregard during pre strike shifts.
First of all, for the left and right parts to be mirror images of one another, the dies they were made from have to be identical, both when new and after they have worn. I would agree they were usually very close, but not always. There is the phenomenon of ‘37/‘38 Chevy rear fenders.....known to be very difficult to get the same relationship on both sides between the wheel opening and the tire. Was there a difference in the dies for the fenders or the dies for the quarter panel, or both? “Specs” are typically given in the desired dimension (nominal) but usually have a range of acceptable + or - variance. Get a stack up of tolerances among the parts in an assembly, all too big or all to small, and it can have a significant effect on the product’s fit or performance. As for the Dodge truck tool box lid clearances........they are “tool boxes”, typically for Tradesmen and Lexus door gap standards may not be appropriate. Imagine the carpenter coming into his dealer....”hey, what are you going to do about all the chipped paint on my tool box openings and lids?” or “hey, they damn lids fit so tight, every time it snows or rains the damn things are frozen shut and I can’t get to my tools !” Not everything is what it seems at a glance. Ray
Every part of every vehicle has a variance or a range which it must hit. Obviously there is a perfect number then there will be .xxx +/- what you are asking us is going to be a guess at best unless someone has the sheet or sheets from the book or original prints. Make sure that your suspension components are square with the world and build from that is the best I can tell ya.
that's what i'll end up doing to be honest, i just find it strange how one side of the truck seems to be off that much the fender is a factory ford half ton fender (i should know i bought it) and its not bent inwards or outwards on either side of the truck.
After the war there was a shortage of new vehicles. So if they could get it out the door it would sell, no problem. The other thing to remember is Fords and Chevys were the lower priced cars and trucks. So if they could get it on the vehicle it went out the door. I have had 46 Ford cars that the rear wheel opening was as much as 1 1/2" different from side to side. And I have yet to see a stock 49 Mercury that the right front fender didn't have at least a 1/2" gap where it met the door
I have spent weeks getting the door gaps correct on 1947-1955.1 Chevy and GMC trucks. Trucks were meant to work hard, until dead, and then scrapped. If it made it down the line, and ran well enough to get on the car hauler, it was done.
Well there is no such a thing as a 1/4 ton fender so if it is wider than the other fender or narrower it is probably not an original fender or the other one isn't. What happens a lot with older cars/trucks like these is that the body/sheet metal gets jostled. A lot can be done with moving it around, you start at the mounts and work your way out. I am not there and you know lots more about what you got than I ever will but perhaps a properly placed shim or two will cure a lot of it.
I don't know about that. I have lifted a few that had so much weld, patch panel, and body filler in them that they might have been getting close...
Working Govt construction jobs, 1/4" was within spec. As long as we got it within a 1/4", we got paid. Maybe carmakers do the same?
Maybe start with parking it on level concrete then hanging a plumb Bob off each corner. There are frame diagrams online for some model years with reference points.
Within Spec simply means it isn't the best it could be but its still within the original manufacturers specification. An example in an engine might be a bearing journal on a crankshaft. When manufactured it was specified that the journal must be 3.500 diameter with a + .0000 -.0100 (exagerrated for this example)tolerance. That means it can't be any larger than 3.500 (+.0000) but it can be 10/thousandths smaller and still be acceptable. So the crankshaft can be anywhere between 3.500 and 3.490 and be "in spec". What this doesn't tell someone is that it may be right at the edge of the tolerance and will soon be "out of spec". Its a technical way to tell you the truth without actually telling you the truth. In some cases it may not matter as far as future failure goes. In the case of a sheetmetal part it simply means a bad fit and you probably have little you can do because you can't quantify the poor fit unless its totally unacceptable. Last year I bought some replacement panels for an old Chevy truck from a big time supplier. The left side step fit just fine, but the one for the right side did not line up at all. Was going to have to split it and weld a wedge patch in it. I took pictures of the problem and called the company. Apparently I was the only one who ever said anything. About 6 months later another replacement showed up in the mail.......so I guess there really was a problem. In the case of an engine, the term "within spec" is a lot more important. Think of it like a tire. The spec says the tire is usable as long as it has .050 tread left on it. Your tire has .051 left on it. Yep, its in spec today, but not for long. Besides that, people who use that phrase often lie even if its slightly out of spec and they are responsible $$$$$.
They might have been nice when the dies were brand new. Once somebody crashed the dies, all bets are off. Some poor maintenance guy had to put the pieces back together, weld it up, and grind it to look like a die....all while somebody is screaming about downtime. I have heard there are certain late 50's fords that have one of the wheel openings in different spots due to a really bad die crash/ugly repair.
Hmmm....just wondering if you have half ton fenders on both sides. The wheel openings on the big truck fenders are larger than the half ton trucks. The big truck fenders are actually slightly narrower than the half ton fenders due to the opening starting higher up on the curvature of the fender. If one of the fenders is for a big truck and the other fender is for a half ton, that may be the reason for the measurement difference...?
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