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October 2009 4x4 Truck Repair Questions - Techline

Willie Worthy | Writer
Posted October 1, 2009

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Wants Ford NP 435 To GM 205 Adapter
Question: I need help finding an adapter. I have a Ford New Process 435 transmission and a GM 27-spline New Process 205 transfer case. I can't find anyone that makes an adapter for this. Could you please help me? The only other thing I could do is to have one made, but this boy's pockets don't run that deep. I have a GM Dana 60 front end and a GM Corporate 14-bolt in the rear, so a Ford New Process 205 transfer case is out of the question.
Steven Rowe
Phoenix, AZ

Answer: I spent a lot of time trying to figure this one out. Problems arise because I believe that the 27-spline GM case you have uses an 8-bolt pattern and the Ford stock adapter uses a 6-bolt pattern. Ford's output is a 31 male spline. I think that it is possible if you locate a 32-spline 6-bolt GM case (used with the '85-91 SM 465 or TH 400 trans) and swap the female spline out for the Ford style, as the bearing bore size should be the same. Then I took some time to look at Off-Road Design's website (www.offroaddesign.com), and discovered under "doubler and custom rotations and hybrid applications" that they have a way to solve your problem, so you should contact them.

Ram 6.7 Turbo Fouling
Question: I own a 2007 Dodge Ram 2500 Quad Cab pickup with the 6.7L Cummins diesel. My problem with it is that I have had it in the shop for three turbochargers in 15,000 miles. I bought this truck to tow a Cedar Creek fifth-wheel. The dealer informs me that the factory says, "I need to beat on it more." Is anyone else having this much trouble with theirs, or do I have a lemon? I won't make any changes to the truck right now, as it appears I will need the warranty. If they keep replacing the turbo instead of finding out what is causing the soot buildup, they will be spending about $20,000 on the truck during the 1,000,000-mile warranty. Pretty stupid on their part, but any assistance or advice you could give would be greatly appreciated.
John Knobloch
La Plata, MD

Answer: No, you don't have a lemon. This seems to be an ongoing problem with the new 6.7 diesel. Your dealer's mechanics and service writer aren't reading their service bulletins.

Have the service writer look up Technical Service Bulletin #11-001-08, which involves the cleaning of the turbocharger to address excess soot accumulation. The procedure cleans the internal components on the exhaust side of the turbocharger. Unfortunately, the Dodge engineers don't really seem to have an answer as to why the soot accumulates, other than possibly a bad O2 sensor that is causing the engine to run too rich.

High- vs. Low-Pinion Gearing Hassles
Question: This is my first 4x4 to off-road with. It's a '75 Ford F-250 with a 460 big-block, NP 435 four-speed tranny, NP 205 transfer case, Dana 60 full-floater rear with 4.10:1 gears, Dana 44 front with matching gears, and 38-inch Interco TSL tires. When I bought it, I broke the front Dana 44 (it was a closed knuckle) and so I bought a new Dana 44 (open knuckle) with 3.54:1 gears in it. Now, I can't get the 4.10 gears to match up in the housing. The closed knuckle is a low pinion and the open knuckle is a high pinion; would that have anything to do with it? I know about the carriers being different sizes and have already set the shims for it. Also, the open-knuckle 44 is reverse-cut-would that also be a problem?
Aaron Dollman
Hilliards, PA

Answer: Yep, you have a problem-actually, two problems. First, high-pinion differentials take a different ring and pinion gearset than a low-pinion differential does. The second problem is that a 4.10:1 gear takes a different carrier than a 3.54 gear does. You can't correct the difference with shims behind the bearings to move it over. You must have the correct carrier. So it's time to re-order the correct parts.

Ford AOD Tranny Tips
Question: I have an '86 Ford Bronco with a 302 EFI V-8 and an AOD tranny behind it. I burnt out the Overdrive and need to replace it. What is the difference between my transmission and an AOD from an '89 model? I can't find anything out online, so hope you can help.
James Talliere
Virginia Beach, VA

Answer: The '89 AOD will work in your '86. There are things that a trans shop can do to improve it in the form of upgrades. You can swap newer geartrain components for better gearing.

Overdrive is this transmission's weakness. There are companies that make high-performance bands and high-performance servos for it, which are a good idea.

Just like a 700R4, the AOD throttle cable adjustment is vital to this transmission's life. It is not just a kickdown cable! Do not drive around with it disconnected or broken.

Wants Scout Diesel To Cherkoee Swap
Question: I have a 1980 Scout II diesel four-speed that I bought new and ran until the body fell off. I have been storing this vehicle hoping that someday I would "get around" to going through the truck and installing a fiberglass body kit.

Current economic conditions and parts availability have me thinking I'm not going to be able to do the Scout the way I wanted to. So as a form of project triage, I have considered pulling the SD-33T engine (doing my engine mods) and setting it into a Cherokee or other Jeep product of similar size and weight (as the Scout II) that had an inline-six engine.

This is where you come in. Since I have been basically anti-Jeep my whole life (nothing personal), I have no Jeep knowledge.

What years of the Cherokee might be the most suitable for the transplant? What will bolt to the SD-33T? My goal is to make a neat, safe, semi-emissions legal, long-lasting, fuel efficient, simple daily driver with an overdrive, lockout hubs, four-wheel disc brakes, 15-inch wheels, easily available parts, and at the same time not create an overly expensive fiasco.
A.D. Nachbar
Wilton, CT

Answer: My opinion is that it is not a very practical swap for several reasons. The Jeep Six is about 29 inches tall from oilpan to the air filter housing, and the length is about 25 inches from fan mount to bellhousing mounting flange. Now go measure your diesel. My tape says the height is 32 inches and the length is 36 inches. I am going to assume that you have already peeked under the hood of a Cherokee. Already have problems, right? Even if you modified the bulkhead that supported the radiator, and moved the radiator in front and against the grille, you're still going to be a bit short on room without modifying the firewall. My guess is that the stock radiator would also be marginal.

Here is the next problem: the AMC engine weighs in at about 500 pounds. Got any idea what the diesel you want to swap in weighs? My sources say some where between 780 and 800 pounds. That's about the same weight as the IH 392. Wow! Three hundred more pounds on the front axle. It's no wonder that Scouts came with heavy-tubed Dana 44 axles. I think that the extra 300 pounds might not be compatible with the Dana 30 front end. Plus, you would have to go to heavier springs to compensate for the additional weight.

Now we have transmission/transfer case problems. Okay, you can bolt up a Chrysler 727 automatic to the diesel-that is, if you can find the special adapter ring that goes between the transmission and the engine. My understanding is that there were only about 1,500 of these ever made. Okay, you don't have to use an auto trans if the Jeep you decide to use came with a manual. However, there are no adapters to the IH bellhousing. Part of the problem is that International used a very long-input transmission shaft, longer than anyone else's. So you're pretty much stuck with using the IH transmission, like their version of the T-18 or T-19. All you have to do is fabricate some clutch linkage. There is a company called Jesco (209/537-5057) that has a lot to do with the Nissan diesels, and they just may have a transmission/transfer case solution.

What do you do about the transfer case? Nothing wrong with the Dana 300 that you have-in fact, it's a really nice unit. Well, there's nothing wrong with it other than the front driveshaft comes out the passenger side and the Jeep differential is on the driver's side. Two ways to solve the problem. Order up one of those "flip kits" that will flip the 300 so it's upside down and puts the front output on the correct side. Or, perhaps even better yet, you could cut all the suspension brackets off the Jeep Dana 30 and weld them onto the Dana 44 that you have left over from your Scout. I am not really sure how the front axle will clear the steering components, but that can all be worked out with a bit of blood, sweat, and tears. While you're at it, you might as well swap in the rear axle, so you will have a matching bolt pattern for the wheels.

Still want to do this? I sure wouldn't.

Tech Letter Of The Month
Ford V-8 Gas For Diesel Swapping
Question: I had an '89 F-250 truck with a 7.3L diesel and a five-speed tranny. Is there a gas engine that will bolt up to the five-speed? I'd like to put it in my '79 F-350, which has a 351M with an automatic.
Mark Brooks
Hogansville, GA

Answer: That is kind of a hard question to answer because of several variables, and in reality, it's not really a good swap. I have to assume that what you want to do is put the five-speed from the '89 diesel into the '79 with a gas motor. I consulted with transmission expert Charlie Correll, and he offered some great advice and some pretty straightforward answers.

First, we have to assume that the five-speed that you want to use is the ZF 4x4 model. Correll says that there are three types of ZF5 Ford-style transmissions. As I am sure you have noted, the bellhousing is part of the transmission. These would be for the diesel, big-block, and small-block gas engines, all of which are different. The diesels, being built by International, have an IH bolt pattern and therefore used a special factory adapter. The starter bolts into the adapter on the diesels and into the transmission on the gas motors. So as you can see, the diesel ZF5 just won't work with any gas motor.

Well, that is not exactly true. If your heart is set on the five-speed and you want to keep the 351M, then you're going to have to find a transmission that was behind a big-block Ford motor. Then you're going to need a flywheel that matches the engine and will have to install a pilot bushing in the crank. Just hope that there is a hole in the crank for the bushing to slide into, as some motors equipped with auto transmissions never had this hole drilled. The pressure plate can be an 11-inch one designed for the T-19 four-speed. Correll provided the following Auto Zone part numbers: Clutch disc (p/n CP31103A), which is splined for the ZF shaft (11/4-inch) and has the springs in the hub (the "A" on the end of the part number stands for "anti-vibration" = springs in hub); pressure plate (p/n CA31055), which is the deeper one for the SMF; throwout bearing (p/n 614062), which has the big center bore for the ZF and a face profile compatible with the release fingers on the SMF pressure plate.

Don't forget there still is a lot of work ahead. There is also the matter of finding the pedal assembly, as you will need a clutch pedal for the ZF5, along with a master cylinder and slave cylinder and the connecting line. Also, you will need a ZF5 clutch fork and a ZF-style starter motor. Hopefully you will find a ZF trans from a 4x4, or otherwise you have to decide what transfer case to use. Keep in mind that the ZF most likely needs to be rebuilt if it was behind the diesel for any great number of miles. The ZF is noted for weak synchronizer rings, and they should be replaced only with Ford parts, not aftermarket pieces. Oh, one more thing: The ZF five-speed takes a special lubricant, not 90-weight, which is similar to a synthetic ATF which will also work.

When it really comes down to it, the payback in dollars spent by getting better fuel mileage will take a long, long time. In reality, you're better off keeping your present C6, or if you really want a manual trans, find a T-19 out of a '75-to-'85 Ford truck and grab everything. T-19s are pretty nice transmissions with even a synchromesh First gear, and I believe almost all of them had a 5.12:1 First gear, but there might have been a few that used either a 6.32:1 or a 4.02:1 First.

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