Truck Update 4: Brakes Break Me and My Transmission Sucks

There is nothing more hopeless than suffering from ignorance. At least a man who knows his fate in a given matter, no matter how grim, can cope with the consequences which he will incur.

And somehow, that dramatic opening relates to my F-100’s brakes.

This nightmare all started with my rear drums. I replaced the brake shoes and did a significant amount of learning how these kinds of brakes work. Overall, they really were not any trouble.

Then, my driver’s side front caliper locked up while driving. When I got it home, the rotor was steaming hot. I jacked everything up, pulled the wheel and caliper off, and quickly determined that the caliper was irreparably seized by trying to drive the piston back in with a big C-clamp. The piston did not move in the slightest.

So, I purchased new calipers and rotors, neither of which I really wanted to replace. I also got new brake hoses, pads, and miscellaneous hardware. I attached everything, attempted to “refurbish” the old master cylinder, and got my brother to help me bleed the brakes. The rears did fine as expected, but it did not take long for me to notice that these brand new front calipers were locking up. The rotors could not be turned at all.

I asked several retired mechanic’s what they thought about the situation. The first one said the store may have given me faulty calipers as that is not uncommon in our Chinesium consumer society. So I returned the calipers, under warranty, and got another fresh set. Ran through the same steps above and the new calipers locked up again!

I then asked another mechanic friend what he thought it might be. He said it could be the master cylinder holding hydraulic pressure on the lines. I told him that there does not appear to be any pressure whatsoever, but he said it does not have to be much pressure to cause the problem I was having. This is where the confusion begins.

Over the span of two weeks, I handled four or five different master cylinders and literally none of them fit my F-100! What gives? My friend said you may have to get another brake booster for a master cylinder to mount onto. Fine.

I ordered a stock brake booster and master cylinder combo from a local shop. I removed the older master, booster, and mounted the new booster on the same old brackets. Everything was fine, until I attempted to close the hood. Now the hood would not close! So I returned the kit and considered my many verbal sins after this enraging frustration.

None of my stock replacement parts like boosters or master cylinders fit, so what the heck was going on? Well, looking at the back of the older booster, I noticed a manufacturer name MBM. A quick search online indicates that they make power brake conversion kits; from this I hypothesize that my F-100 was a MANUAL BRAKE truck from the factory and was converted to power brakes probably twenty or thirty years ago. No wonder literally nothing fit.

So I had to order another power brake kit from Summit Racing just so I could get a functioning master cylinder. I ran through the bench-bleed and installation, and finally my front discs did not lock up. I even drove the truck around the block with a thermometer gun, occaisonally getting out and measuring the temperature of the rotors. Everything was finally solved.

Is there any lesson to be had in this story? Perhaps ignorance of even the slightest detail can ruin the best laid plans? I do not know, but it is much like going for a leisurely walk from point A to point B without knowing that between those two points is a landmine. At least I have a pretty good understanding of hydraulic brakes now, but this sure would have been easier if I knew that old booster was not stock.

Three Terrible Gears

After about a week of joyful driving, including passing on the interstate in my wretched F-100 (I do hope I embarassed other drivers), my transmission decided it did not really want to work anymore. It almost left me stranded at a stoplight: I thought I had it in 1st gear, but I could not get into 1st to save my life! Somehow, I was able to grab 2nd, then 3rd, then went straight home.

After weeks of messing around with it, here is what I have determined: my shifter is complete junk, and the transmission itself can’t hardly be shifted even with a wrench under the truck. The shifter is very worn out and it has so much “play” in it that it flops around, meandering for the right gears; I have made what repairs I can, but it simply isn’t good enough. Even if I can get the shifter to behave, the trans itself does not want to shift; as I said earlier, wrenching on it underneath just barely gets it into gear. Further, reverse grinds very badly.

My truck had been doing so well for quite a few months up to this point, but I think the transmission is pretty much finished. Therefore, I am considering some options.

  1. Rebuild the 3 speed. The problem with this plan is I don’t want to invest in a 3 speed transmission at all, because I believe the money is better spent modding a better transmission in. Further, a new shifter is surprisingly expensive, around $600 all up.
  2. Modding in a 4 or 5 speed. This is my favorite option and there are quite a few transmissions to choose from, each with their pros and cons.
    • The classic swap is a T-5 from a fox-body Mustang with a 302, but it requires quite a bit of floor modification and possibly running bucket seats. Also, it is not the toughest transmission around without beefing it up.
    • The M5OD-R2, a 5 speed from the late 1980s and 1990s F-150s, is a gearbox I am considering; my biggest gripe with it is the hydraulic clutch needing to be grafted onto my truck.
    • The ZF5 that fits Windsor block Fords is very difficult to find, and expensive when you do, so I’m not holding my breath. Also, and most suspiciously, everyone on FTE says the ZF5 is bullet-proof, but every listing I see says it needs a rebuild.
    • A new Tremec TKX will cost $3000 minimum. Not keen on that either, but there is no doubt that it is high quality.
    • There are several old 4 speeds that ought to work, like the NP435, T18/T19, or the somewhat rare Ford 3-speed with overdrive. I would probably pick the NP435 or T18 over the others just because they are cheap and very reliable even though they lack overdrive. With my 3.25 rear gear, overdrive is optional.
    • Most of these transmissions will require some driveshaft modifications.

In short, there is no perfect solution to this problem and I’ll have to make a compromise somewhere. The 3.03 3 speed is out of the question since the shifter is so expensive, and I have the wrong steering column so I can’t put it back on the column. The M5OD-R2 and ZF5 both require hydraulic clutches and other screwing around that I’m not interested in. The T18/T19 or NP435 should be nearly plug-and-play as long as they come from a Ford (there are GM and Dodge applications for the NP435); I think I would just need to modify my driveshaft.

The 3 speed with overdrive should bolt up with no modifications whatsover from what I have read; apparently, the trans is about the same length as my current 3.03 so I wouldn’t even need to modify the shaft. I have read however that it is not the toughest transmission around and the last thing I need to do is make the F-100 less reliable.

Anyway, this is turning into semi-ignorant techno-babble about ancient automotive technology. I’ll post when I have made my decision and executed it, and I am open to any advice anyone can offer. Right now, I’ll look for a NP435 or T18 nearby; I may never use granny gear, but if these transmissions were good enough for heavy duty dump trucks and other serious applications, then they should hold up just fine behind my 347. I get the feeling any other swap is going to be complicated enough to warrant the purchase of a parts truck which I definitely don’t want to do.