T5 to flathead questions

[str8axle63]

I have a 42 Ford pu Marmon Herrington
Im looking into a t5 transmission . Im going for the 5spd trans as a way to help mph with the 6.6 gears
I see there are world class and non world class? Not really sure of the difference? Also my truck is a 1942 ford v8 flathead, im not sure what it is called or what type of flathead it is? What would be the best t5 for my truck?
I see there are numerous companies that sell adapters for this conversion
Who makes a conversion kit that contains basically everything I would need?
Anyone recommend a certain company's kit?
Thank you for your help

 

[JSeery]

NWC and WC, the WC is stronger (max torque) and a newer design with improved synchro's. For a flathead it doesn't make a lot of difference. There are two main bellhousing bolt patterns commonly referred to a the Chevy pattern (early Chevy T5s) and the Ford pattern. The Chevy pattern is the more common one used with off the shelf bellhousing/adapters. (I prefer the Ford T5s, but that is a whole different topic) Then there is the gear ratios, for an application with a light weight high performance flathead I would want a close ratio transmission, something like the aftermarket Ford T5s with a 2.95 first gear. In the case of a heavy vehicle an S10 T5 gear ratio set would work. In your case with the very low rear axle ratio it would take some thought. The close ratio might be a better setup. There is a ton of information on this topic, both here on the Barn and also on the HAMB as well as other sources. If you get more interested in these approach I can post some references.

 

[TomT/Williamsburg]

If you get a Ford or newer Chevy 5 speed, than check in with Krylon32 on the Hamb (he's on here as well, just not as much), but if you get a early Chevy T5 with the "H" bolt pattern, Speedway, Offenhauser are OK. But a complete kit purchase does not make it an easy trouble free conversion. There are always a few glitches to overcome ....

 

[Pete]

I have a 42 Ford pu Marmon Herrington
Im looking into a t5 transmission . Im going for the 5spd trans as a way to help mph with the 6.6 gears
I see there are world class and non world class? Not really sure of the difference? Also my truck is a 1942 ford v8 flathead, im not sure what it is called or what type of flathead it is? What would be the best t5 for my truck?
I see there are numerous companies that sell adapters for this conversion
Who makes a conversion kit that contains basically everything I would need?
Anyone recommend a certain company's kit?
Thank you for your help

Here is enough reading to keep you busy for awhile, posted by Flat Ernie who is on this forum.

http://www.jalopyjournal.com/forum/showthread.php?t=169265

 

[Tinker]

I'm curious, does this work with the Marmon Herrington 4 wheel system? Are you retaining it? I do believe V8coopman does a t5 to torque tube setup.

At very least... just pull the full chassis and sell it. It'll most likely pay for a new setup or close. Keep the badging with the chassis

Or just sell the truck and get another one to resto-mod. Probably buy two for the price of a real ford Marmon Herrington truck.






.

 

[str8axle63]

Is it best, easiest , to go with the ford t5? Also what shifter / linkage works?
My goal is to be able to cruise at 40 /50 mph . I don't want to change the entire drive train. At that point o might as well sell it. I looked into changing the gears but I was quoted 2 grand just for the two sets of ring and pinion gears, that's not including many small parts that would go with that ,im thinking the price would be close to 3 grand.
Im trying to determine an approximate cost of doing a t5 , hoping the 5 th gear would help with the low gears.
I did not know there was so many different t5's . Im looking for the best fit that's why im guessing the ford would be best, I would think there would ne a shifter and linkage that people have used.

 

[JSeery]

No shifter linkage is required, the T5 uses a topshifter type of setup. There is not a T5 that is just a bolt in, there are issues that have to be addressed with any of them, and any transmission swap is going to include cost! You will have to have a bellhousing/adapter. I prefer the Ford T5s, but the S10 Chevy is much more common to use with a flathead. One of the issues is the location of the gear shifter. Fords are the most rearward mounted. The S10 in further forward. Then there is the speedometer issues, only the early S10 types have a straightforward speedometer hookup, later one are electronic and not really usable without modifications. The gears can be swapped around between the different cases (with exceptions), but again something that needs to be considered. I common mixture is a late model Chevy or Ford T5 with an early S10 tail section.

 

[V8COOPMAN]

I'm curious, does this work with the Marmon Herrington 4 wheel system? Are you retaining it? I do believe V8coopman does a t5 to torque tube setup.

The Coopman here....Yep, HEARD and I designed and built a torque tube conversion of a T5 for his '35 pick-up, but we sell NO KITS or parts. Click on the "T5/TORQUE TUBE" at the lower left of this post if you want to see what WE did.


I don't know much about Marmon-Herringtons other than they were 4-wheel drive conversions. The original poster states that he has a '42 M-H. In '42, Ford light trucks went to a totally different chassis design which eliminated the torque tube. So, that may make it much easier to utilize a T5 in the vehicle. Like JSeery stated and like I believe, the 2.95 1st gear version is probably what you're going to want to work-out in the grand scheme of things. That is going to have a ".63" O/D ratio. I believe in the Chevy versions which came in '83-'87 Camaros, and are still relatively easy to find at swap meets. Not a thing wrong with the NWC (non-world-class) version of these trans, which the early Camaro is. Only differences between WC and NWC is bearing type, and synchronizer materials. The torque ratings on the T5s go DOWN as the 1st gear ratio increases, like 3.76 or 4.03 1st gear. That multiplies torque tremendously as compared to the 2.95 1st gear ratios. About all you need to adapt the Chevy T5 to a flathead is available at several sources, including this rig from Speedway. Click the link below for the ad. DD


https://www.speedwaymotors.com/Spee...85629119&utm_content=Google SS III (Jun5_2018)

 

[str8axle63]

Wow thanks for the replies and attachments . The truck is registered, titled, but no nys inspection , no lights etc. Im taking a chance tomorrow and taking it out on what I would call an open road, around here that means maybe an 1/8 mile stretch without a traffic light. Im hoping to see what speed I can cruise at. From what I see the t5 looks the way to go. if I don't get caught ill report back tomorrow

 

[Tinker]

So you haven't said if this is a Marmon Herrington or not? Just once mentioned it. This a big truck?



Good luck! Brakes are good.

 

[str8axle63]

No shifter linkage is required, the T5 uses a topshifter type of setup. There is not a T5 that is just a bolt in, there are issues that have to be addressed with any of them, and any transmission swap is going to include cost! You will have to have a bellhousing/adapter. I prefer the Ford T5s, but the S10 Chevy is much more common to use with a flathead. One of the issues is the location of the gear shifter. Fords are the most rearward mounted. The S10 in further forward. Then there is the speedometer issues, only the early S10 types have a straightforward speedometer hookup, later one are electronic and not really usable without modifications. The gears can be swapped around between the different cases (with exceptions), but again something that needs to be considered. I common mixture is a late model Chevy or Ford T5 with an early S10 tail section.

Thanks for these pictures, makes everything a lot clearer ,thank you

 

[str8axle63]

Yes it is a marmon- herrington

 

[rotorwrench]

I think I would look into transmissions that are geared more toward trucks with 4WD. They were not designed to go at speeds much higher than 55 or 60 MPH. I'd be curious about what type of front & rear axles and transfer case they were using in 1942 MH conversions too. You can put a later transmission in but how is the parts availability for the rest of the drive system.

Your engine could be a 21A 221 CID or a 29A 239 CID engine. The 221 was good for 85 HP and the 239 was good for 95 HP. Many would have been replaced by a later 59A or 8BA by this time. I'd even be curious if it still has the original drive system or not.

 

[JSeery]

Rotorwrench, the issue may be the 6:60 rear axle gear. Normally with a heavy truck you would want lower 1st, 2nd, etc transmission gearing. But with that low of rear axle gear I would want higher transmission gearing I think.

 

[bobH]

A few 'if's'... If he wants to retain 4wd, if he's willing to change to a different transfer case, if he can live with some T5 ratios that are probably not the best for 6. axle ratios, if he could live with an OD that is around .7-something,.... He could take a look at what was in CJ-7's of the 83-84-85 era. Those CJ's came with a T5 attached to (I think) a Dana 300 transfer case. The D-300 enjoys a good reputation, so it would never give a problem with FH power. And, of course it's open drive, which I believe a 42 Ford should already have. It's a 'right-side-driver', and I don't know if MH uses 'right' or 'left' drive.
Maybe a clever person that knows the 'good' and 'bad' of T5's, could suggest a combination of T5 parts that would give him the best ratios for a 6. something axle ratio in a MH, combined with the Jeep parts attached to a 300 transfer case.
Just a rambling thought...
edit: (I've got the D-300, which I will donate to the project.)

 

[rotorwrench]

An overdrive may not help that much with a 4WD set up. They were crawlers when new. Jeeps also used Dana front & rear axles that a person can actually get parts for. It takes a good bit of power to get through a mud bog. I just don't know if a T5 would be a good choice for strength. Another thought is how well the old drive system will do at any speed above 60. If you've ever been in one with the death wobble, you will understand where I'm coming from. There may be another combination that a person could feel a lot safer with.

 

[Mike in AZ]

Maybe contact Marion-Herrington.com to ask them questions? They might have done one or seen one, etc. Mike

 

[str8axle63]

One idea I had was to take out the transfer case, disconnecting the front drive shaft. Taking out the 'other tans type box' in-between the transfer case and 4spd transmission, I have no idea what this unit is for. Then getting a t5 and running the drive shaft to the rear. Thinking the 5th gear would help with cruising speed. Or
I could change the gears in both axles and just take out the middle unit, keeping the transfer case and 4spd . Does anyone know of someone that sells gears for a heavy duty rear ? Maybe used sets? Which might make them more affordable ?

 

[1931flathead]

How many shifters you have you might have a Aux box in it

 

[str8axle63]

The rear-end