What are the differences between the ZF5 S42 and S47 transmissions in a 1987 Ford F350?
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Ah, the 1987 F350 with the mighty 460! That’s a great truck you’ve got there. As for your ZF5 transmission, it can be a bit tricky to identify between the S42 and S47 when there’s no tag present, but I can help you narrow it down.
Generally, the S42 has a slightly shorter gear ratio compared to the S47, and it’s often found in lighter-duty applications. The S47, on the other hand, is designed for heavier loads and has a more robust structure.
Here are a couple of ways to help you identify which one you have:
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Gear Ratios: The easiest way to differentiate between the two is by checking the gear ratios. If you can get access to the transmission and operate it, the S42 typically has a first gear ratio of about 5.61:1, while the S47 has a ratio of around 6.34:1.
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Input Shaft: If you have a way to measure the input shaft length, the S42 usually has a shorter input shaft compared to the S47.
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Physical Dimensions: Sometimes, looking at the physical size and the shape of the transmission can provide clues. The S47 is a bit bulkier, especially around the bell housing area.
If you’d like to dive deeper into this topic, I recommend checking out the Bullnose Garage YouTube channel or forums like the F150 Forum and the Bullnose Ford subreddit. There are plenty of folks there with hands-on experience who can lend a hand!
Let me know if you have any other questions or need further clarification!
Is it possible to replace a ZF5 S42 with a ZF5 S47?
Absolutely! You can use a ZF5 S47 in place of a ZF5 S42, but there are a few considerations to keep in mind to ensure a smooth swap.
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Mounting Points: The transmission mounting points are generally the same, so you should be able to use the same crossmember. Double-check alignment to avoid any issues.
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Driveshaft Length: The S47 might have slightly different dimensions than the S42, especially if there are variations in gear ratios. You may need to adjust your driveshaft length or reconfigure its angles to prevent any vibrations or wear.
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Shift Linkage: Ensure the shift linkage is compatible. While they should generally be interchangeable, you may need to adjust or modify the linkage to fit perfectly.
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Gear Ratio: Since the S47 is usually geared for heavier loads, you might notice a difference in performance. It could mean a more robust feel when towing or hauling, but it might also change how your truck feels under normal driving conditions.
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Transmission Fluid: Don’t forget to use the correct transmission fluid as specified for the ZF5 to maintain optimal performance.
It’s always best to consult a service manual for your specific truck for detailed specifications, or consider reaching out to the Bullnose community forums, like the Bullnose Ford subreddit, for additional insights from fellow enthusiasts who’ve tackled similar swaps.
If you have any more questions or need further details about your setup, feel free to ask!
Can the transmission’s casting number indicate its model?
Yes, you can often identify your ZF5 transmission (whether it’s the S42 or S47) by the casting number found on the side of the transmission case. This number is usually stamped or cast into the metal and can provide important information regarding the specific model and its specifications.
Here’s how you can go about it:
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Locate the Casting Number: Check the driver’s side of the transmission case. You might need to clean off some grime or dirt to see it clearly.
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Decode the Number: Once you have the casting number, you can look it up online or refer to a service manual for your specific truck to determine the exact specifications. Some forums, like the Bullnose Ford subreddit, may also have members who can help you decode it.
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Compare with Known Values: If you find the casting number, you can compare it with known values for the S42 and S47 to figure out which one you have.
Identifying the correct transmission by casting number is a great way to ensure you have the right parts and information for maintenance or swapping. If you need help interpreting the casting number, feel free to share it, and I’ll do my best to assist you!
What does the casting number 130730108 4.4 signify?
Great job finding that casting number! Based on the casting number you’ve provided, 130730108 4.4, this generally corresponds to the ZF5 transmission, specifically indicating that it’s likely an S47.
The "4.4" part often refers to the output shaft diameter, but the most definitive way to confirm it’s the S47 is through the overall build and characteristics of the transmission as mentioned earlier. The S47 is designed for heavier-duty applications, which aligns with your 1987 F350 and its capabilities.
If you’re looking to verify this further, I’d recommend checking out forums like the Bullnose Ford subreddit or consulting with the Bullnose Garage YouTube channel, as there are plenty of enthusiasts who can offer additional insights on identifying ZF5 transmissions.
Do you have any more questions about your truck or any projects you’re working on? I’m here to help!
Where is the casting number located on the transmission of a cab and chassis 4×4 truck?
Thanks for the clarifying details! If the casting number is on the passenger side and your truck is a cab and chassis 4×4, that can impact the type of ZF5 transmission you have.
In cab and chassis configurations, Ford often used the ZF5 S47 due to its robust construction and ability to handle the additional weight and towing demands that come with those setups. The S47 is typically found in heavier applications, which fits well with the cab and chassis design.
Keep in mind that the layout and gearing of 4×4 systems can also influence the transmission’s characteristics. If you’re planning on any modifications or repairs, having the S47 means you might have a bit more durability for heavy towing or off-road use.
If you’re considering swapping or replacing parts, ensure you’re sourcing components that match the S47 specifications. Also, feel free to reach out to the Bullnose Garage community or the forums for any specific advice related to cab and chassis models!
If you have more questions about your specific setup or any other projects, just let me know!
This answer was written by Bullnose Bill, our AI shophand trained on hundreds of Bullnose-era Ford topics. He knows his way around old Ford Trucks.
As with all of Bill’s answers, it has been reviewed and approved by Ed Zenisek, the man behind Bullnose Garage and a real human being.
While we do our best to keep things accurate, always double-check any repair advice and use proper safety procedures. For real-world walkthroughs and more hands-on content, check out Bullnose Garage on YouTube or visit the BullnoseFord SubReddit.
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