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Isuzu reliability tester
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Discussion Starter #1 (Edited)
Hello all this is my first post but I have been looking around here for a little while,I think its time to get my feet wet.

I have a 67 ford F100 single cab short bed 2wd. I love these trucks especially since this was my first vehicle. I would like to take the 300 6 cylinder and 4 speed manual out to install a 4bt with xx trans (unsure of the trans).

I have been looking at putting a front suspension from an 05 crown vic police car withh 39,000 miles in since it has 12" power disc brakes, power rack and pinion steering, and IFS. I will also be installing the crown vic 8.8 rear axle with disc brakes and 3.55 gears.

The questions I have

1. What do you think of the front suspension? Will it handle the 700 pounds of the 4bt? remember it is designed for police duty with a 500 pound 4.6L engine.

2. What trans do you recomend with the 3.55 gears? auto or man? which kind?

3. Are the 3.55 gears ok or should I change them higher or lower?


The truck will be used for towing a 5000 pound lawn & garden trailer and will also be used for general cruising around to help keep some miles off of my 06 chevy, hence the reason for the better suspension and bigger brakes.

I am mainly wanting this swap for the mpg and reliability of the diesel since this truck is paid for I dont mind spending 5k or so. Would that get the swap done?

Thanks
Randy
 

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Welcome!

Just my opinion for whatever it's worth: I'd stick with the stock front end and simply install one of the disc brake conversions. The Vic's springs will be about 300lbs too light for the 4BT & tranny combo. With the right leaf springs & shocks and proper alignment that old Ford can handle really well, without the Vickie upgrades. My '67 Dodge fullsize truck has virtually the same axle/suspension and it handles great, enough that it needs stickier tires to keep up with itself!

I would suggest power steering and power brakes if it's do-able.

I'd check some of the gear ratio calculators to figure your final drive. Either you'll have a 1:1 top geared or o'drive top geared tranny. Impossible to suggest a final drive axle ratio without knowing which you'll be running.

Mine's NV4500 o'drive with 4.1 rear and about 30" tires. It's just about right for the towing you suggest.
 

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Isuzu reliability tester
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Discussion Starter #3
The reason I was thinking about useing the crown vic front end is because of cost as well as modern technology. I can get the entire front end for $250 and it is in excellen condition and add air bags for another couple hundred, that is less than it would cost to upgrade to disc brakes on the current suspension and I get rack and pinion with it and an aluminum front crossmember.

As far as the tranny thing, I am not sure what to use. I have thought of a 5 speed ford auto out of an 03-06 6.0 powerchoke. I have also thought of a 5 speed manual out of a dodge truck or maybe a 4L85E. I can use a pcs controller to control the autos. What do you think of those?
 

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Have you seen FORDification.com? There is always a ton of discussion there about front suspension.

The hands down final conclusion is always that you cannot beat twin I-beam suspension for anything short of road racing the thing. It handles great, it's 10 times tougher than any arm suspension and disc brakes are a very cheap and simple upgrade. I believe you can even use the twin piston calipers and mounts off the light duty F-250 2wd trucks on them if the normal single piston setup doesn't do it for you.

I put quite a few miles on a 1970 F-100 2wd with 79 F-150 discs on it, non-power, just manual brakes. I put a 1991 EFI 4.9 six in it with the stock T-18 and 3.50 rear. That truck would tow far more than what the 1/2 ton frame would handle with power to spare. It also had no problem stopping. I pulled a 6000 pound highboy with 2000 pounds of crap in the bed with a towbar behind that truck 250 miles once with no problem stopping and pulled a 5500 pound diesel genset behind it a few times with the same results.

The 4BT is a real easy swap into a bumpside. I'd keep your 3.50 gears and run a ZF or M5R2 5 speed.
 

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I've never paid a dime for the parts to convert I-beams to discs and don't think many have paid more than $50 for them. The stock 68-79 2wd power steering boxes are real tough and work very well.

The only upgrade I would even consider for a stock I-beam front end with tight pins and good bushings would be an F-250 or 350 camper special sway bar.
 

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I agree, don't cut your truck in half!!! Those are good front ends. If you put power steering on it, (and I do recommend you do) you will have to change the steering column also if I remember correctly. Its is about 2in. shorter than the non P/S column. Its been about 30 years since I've done one of these but this is what I remember about the swap. The idea of putting the sway bar on it is a great one. I think in the long run It will be cheaper to go this way than with the clip and much, much easer. Those bodies in SWB are getting a little hard to find and look great. Id try to keep it looking stock as possible. That is what Im doing with my 64 IHC short narrow bed.
 

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Isuzu reliability tester
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Discussion Starter #7
yes I have seen that website, I have even tried registering there but cant get the email notification to be sent to me. oh well. I have checked into buying the parts needed to convert to power front disc brakes and power steering. I can promise you it is alot more than $50.00. I am also not a fan of the i beam suspension sorry just my opinion. I could dump a bunch of money into it to make it the way I want it if I had to but I would rather start with a better suspension. If I have to use the i beams to support the weight then I will but am trying to keep from doing that.

So you think the the zf or the m5r2? any idea which should be cheaper? What about adapter plates will these bolt up to a 4bt out of a chevy? is there a big difference in mpg between a manual and auto with the 4bt?

Thanks
 

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the Crown vic front suspension WILL NOT handle the truck much less the added weight the 4bt will be giving up the power disc breaks are smaller then the F-150s not to mention yo you will have to hack into your truck to do it? if you really want to convert to a Arm style front look at a chevy unit with coils however I have had bad experiences with these too if it were me id Keep the twin I-Beam go to the junk yard get some discs for it and if u need more weight handling capability throw in a set of F-250 or 350 coils they bolt in!!! other then that put the like 4 bushings that are all in a Twin I beam setup it is dirt simple rugged and cheap as far as rear ends go stay with the 9" too its better then the 8.8 in almost every way!!! 28 spline will last but if your worried go with the 31spline unit it is also way easier to swap gears to try different ratios out and more choices for gears and or lockers if you want discs on the rear if you have a big bearing 9" the backing plates and disc setup off of a 8.8 bolts up as well your truck has all you need!!!! FORDS RULE!!!!
 

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The complete power steering box, firewall plate and PS steering column is like $75 from U-pullit. There are always 10 of them at any yard I go to locally. If that doesn't work for you ebay is full of them too.

If I bought just the disc brake spindles used from a wrecker and bought everything else brand spanking new with no cores to return I'd have less than $400 in everything, rotors, bearings, seals, kingpins, calipers, lines, etc. brand new.

Or I could just buy the complete front suspension from under any 73-79 F-100 off craigslist for $50.

Why don't you like the I-beams? I mean, I've heard some pretty funny explainations from people in the past about how they think they're impossible to align or wear tires funny and it seamed there experience was with a 200K mile farm truck that had never seen grease since the day it was new.

Ford's I-beams are the best light truck front suspension ever made. The only downside I can think of is lowering, but spend the bucks on some good beams and that's not even an issue.

For a Ford swap a chevy 4BT doesn't do you much good. The Ford 4BT's have the easiest to adapt mounts and bolt to windsor/six transmissions. The M5R2 has great ratios, is dirt cheap and holds up fine to a lighter truck and mild 4BT power. The ZF has much wider ratios, but a taller overdrive. The zf will take anything a 4BT could dish out though.

For an auto you could adapt any late model transmission you could get an adapter and aftermarket controller for.
 

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Check the track width on that Crown Vic and compare it to the truck. I bet the Vic is several inches wider. If you have to hack the frame to put the crossmember in I vote NO! One thing you can do to get as much weight off of the front suspension as possible is to place the motor back, toward the firewall, as much as possible. I have a LOT of room from my radiator to motor.
 

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Isuzu reliability tester
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Discussion Starter #12
ok guys I am not trying to have an attitude so dont take it that way but, you might want to do some research. The crown vic will take the weight of an f100 with a big block in it. There are several people that I know of that have done it and several on the net with everything from the 4.6L to big blocks I just didnt know how it would handle with a 700 pound 4bt. The track with is almost perfect for the 67 f100. There is no frame hacking involved it is almost a bolt in deal. You have to take the front crossmember and all suspension components off the truck then the crown vic crossmember bolts in using two 3/4 inch bolts per side, from there all the suspension components bolt to that. I planned on boxing the frame at the same time.

I guess what I am trying to say is that the crown vic weighs a little more than my truck does right now (my truck 3950 crown vic just over 4k) and the engine in the crown vic weighs about 500 pounds the 4bt weighs 700 pounds. does anyone think that the 05 crown vic suspension will crumble with an additional 200 pounds. The crown vic is used in road race apps beleive it or not LOL, even with the added weight of superchargers and other parts in the engine bay to add weight, and the suspension seems to take it fine.

Once again I am not trying to start an internet argument and I value all opinions given, I am just trying to express mine and get good conversation going on.

I just want to get all my ducks in a row on this swap before I get started and figured you folks would know.

Thanks
 

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Sounds like you have your heart set on crown vic stuff. Go for it!

If you use your truck like a truck, an easy conclusion to come to considering you're putting an industrial diesel engine it, I wouldn't bet a dime on that car suspension holding up. If you never haul anything in the bed and plan to dodge potholes and use the truck as a car then put the car suspension under it.
 

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I own a Crown Vic retired police car and it's my daily driver. The weak points will be the ball joints & tie rod ends. Compare the original truck sizes of these components with the car size components. Sure it may initially work but for how long or how safely?
 

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I would not have any reservation about using the Crown Vic clip . I run a Mustang II front end in my 66 F-100 ( 4BT- M5OD ) , and with 450# rate springs it , it handles the weight fine
Rick
 

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The track with is almost perfect for the 67 f100. There is no frame hacking involved it is almost a bolt in deal. You have to take the front crossmember and all suspension components off the truck then the crown vic crossmember bolts in using two 3/4 inch bolts per side, from there all the suspension components bolt to that. I planned on boxing the frame at the same time.
I am not experienced with the F100. If the Vic front suspension goes in that easily it may be a good swap. Years back the Dodge Valore suspension was popular in the 50's Ford trucks. This may be a similar swap that I was just not familiar with. When boxing the frame make sure you let holes to access the bolts. Let us know how it works!
 

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The weak part of the 65-79 F-100 and F-250 2wd frame is the driver's side frame rail just forward of the steering box where the crossmember is riveted in.

Under really hard use with a heavy engine (460) the frame will crack there. I've never seen or heard of a bumpside (67-72) frame cracking, but have seen several dentsides (73-79) with 460's have issues there.

The 4x4 frames are completely different and the F-350 2wd frame is the same as the F-250 4x4 frame, just with a crossmember for the I-beams and coil buckets.

The F-100 frames are pretty thin. They twist and bend pretty good with a heavy load. Boxing would probably help a lot if done right.
 

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I believe the 700 lbs weight estimate is incorrect. Far as I know a 4BT weighs 750 bone dry, no flywheel, then add in a whole bunch of oil, plus adapter plate, flywheel, clutch, and a maybe heavier tranny. My NV4500 trans alone weighs 200 lbs.

I put new Eaton Detroit front springs on my truck. It had springs for a V8 Poly, a heavy engine, and I got brand new 250 lbs heavier springs per side. That is, I increased front spring capacity 500 lbs total. It is just enough to be equal ride height with the Cummins/NV4500 and adapters, clutch, flywheel etc. That's with the engine set back as far as it will go, after cutting firewall back an additional 3".

However, like the do-it-yourself surgeon said, "Suture self..."
 

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Isuzu reliability tester
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Discussion Starter #19
well I have decided to try the swap. I am going to buy the whole crown vic for $1500. That will give me a 2005 crown vic police package with 39,000 miles. I am going to do the conversion of the front crossmember power rack disc brakes and I will also use the 8.8 rear end. After that I will part out the engine tranny wireing, interior, etc to make all or most of my money back. I will put the 300 six cylinder back in for now to see how everything goes. While I am driveing that around I will be looking for a good used 4bt then swap it in and see how it goes. I will take lots of pics and keep everyone informed.

I still havent decided on which trans I will go with for the cummins engine I have been thinking about the ford 5spd auto out of the 03-06 f250's.

Oh one more thought. Would it help to add a second crossmember made of steel in front of the aluminum crown vic crossmember for added strength? that along with the partially boxed frame should be good I hope.
 

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Discussion Starter #20
I would not have any reservation about using the Crown Vic clip . I run a Mustang II front end in my 66 F-100 ( 4BT- M5OD ) , and with 450# rate springs it , it handles the weight fine
Rick
Rick, you are my hero. I was hoping someone out there had done this before. I just get tired of people always telling me my ideas cant be done. I always finish projects like this just to prove them wrong, its a great modivator.

Would you do anything different with your front suspension with the 4bt in it?

Thanks, you have really boosted my confidence in this project
 
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