Ford & Chevy transmissions

[BajaFand]

I have a '71 Ford F-100 project that I am just starting to get underway. With my F-100 came a brand new looking freshly rebuilt C-6 transmission ready to go with the acception of a torque converter, but no engine. I just bought a Chevy 350 engine for it this weekend. I want to switch out the C-6 for either a Chevy TH-400 or 700r4. My question is: is it worth the hassle switching the Ford trans for a Chevy trans or should I just get an adapter plate to bolt the 350 up to the C-6? Assuming there is an adapter plate for this application? Also, I'm a Chevy/Toyota guy so I don't know the first thing about a C-6. Are they 3-speed or 4? How much could I sell it for? Would it be worth it to trade straight across for a TH-400 or 700r4 of the same condition/quality or would I be getting ripped off if I did that?

[Big Oly TT]

I have a '71 Ford F-100 project that I am just starting to get underway. With my F-100 came a brand new looking freshly rebuilt C-6 transmission ready to go with the acception of a torque converter, but no engine. I just bought a Chevy 350 engine for it this weekend. I want to switch out the C-6 for either a Chevy TH-400 or 700r4. My question is: is it worth the hassle switching the Ford trans for a Chevy trans or should I just get an adapter plate to bolt the 350 up to the C-6? Assuming there is an adapter plate for this application? Also, I'm a Chevy/Toyota guy so I don't know the first thing about a C-6. Are they 3-speed or 4? How much could I sell it for? Would it be worth it to trade straight across for a TH-400 or 700r4 of the same condition/quality or would I be getting ripped off if I did that?

I have a real nice 1973 Ford stepside I race with. I did the last Baja 500 and last years 1000. I would throw a 351w stroker motor in there, but sounds like you are set on the Chevy. The C6 is a 3 speed. The th-400 is as well. My C6 has a gear vendor on it making it a 4-speed and will be a 6-speed in the near future. And you can do the same with a th-400. Most people don't know this. I believe there are adapters for everything (Advanced Adapters, google them?) If you still can't get it, get back to me.

[BajaFand]

Thanks Marshall. I know a good amount about the GM transmissions but the Ford's I don't know anything about. I like the idea of the Gear Vendors setup, it maybe worth a try.

I want to keep the truck reliable so I don't want to do any stroking (atleast not yet). I got the Chevy because it was the first thing to come along for a good price. I am not apposed to a Ford motor at all since it's a Ford truck, but this is what I came upon for the right price. It will also be back-halfed now as well and 4-linked. I was going to keep the full frame for it to be class 8 legal if I wound up with a Ford motor.

[sickrick]

Go one way or the other, chevy engine and trans or ford engine and trans.

Don't bother with the 700r4, TH400 or c6 both are good.

Its a Ford truck so I reccomend the Ford motor/trans combo..

[steveG]

My C6 has a gear vendor on it making it a 4-speed and will be a 6-speed in the near future.

Very cool Marshall! I wish I had the wheelbase to do the same on my Bronco. What's involved in making it a 6-speed?

[EQuin]

The little I know about the C6 is that it is one of Ford's stronger, heavy duty auto transmissions and is relatively cheap and easy to rebuild. I could be wrong, but I believe the C6 came with two different types of bellhousings - one for Ford small blocks and one for the big blocks. Somewhere on fullsizebronco.com someone posted a pic showing the difference between the two. So if you were to order an adapter from Advance Adapters, they may ask you what bellhousing it has.

One good thing about the C6 is that if it's a 4x4 C6 it should bolt up to any fullsize Ford transfer case - the stout NP205, the BW 1345, and the BW 1356. Of course, if you decide to replace it with a Chevy transmission, then you'll probably have to get an adapter plate for the Ford t-case if your truck is a 4x4.

Anyway, I believe the Moss Brothers' Class 3 Championship Ford Bronco runs a C6. Also, one of the midwestern racers, Sickrick, runs one and has recommended the C6 in other posts. You might want to PM Sickrick for more info on it.

Hope this helps.

[EQuin]

Doh! Sickrick posted right before I did.

[BajaFand]

Thanks for the info guys. I got the Chevy motor, so unless things change and I find a Ford motor for a better deal I will stick with the Chevy 350. It sounds like I should stick to a TH400, even though I will be driving it on the street I guess I probably don't need the overdrive.

My trans is a 2WD but I guess I need to find out if it's big block trans or small block trans. I talked to a mechanic today about the C-6 and he said the regular C-6 is just for big blocks and there is another trans called the FMX C-6(FoMoCo experimental) that can work with a big block or a small block. Does that sound right? Anyways, he said a C-6 trans in the shape that mine is in (fresh rebuild with 0 miles on it) is worth around $1000-$1500 depending on if it's the regular C-6 or the FMX C-6. Does that sound about right?

[retroblazer]

I have a real nice 1973 Ford stepside I race with. I did the last Baja 500 and last years 1000. I would throw a 351w stroker motor in there, but sounds like you are set on the Chevy. The C6 is a 3 speed. The th-400 is as well. My C6 has a gear vendor on it making it a 4-speed and will be a 6-speed in the near future. And you can do the same with a th-400. Most people don't know this. I believe there are adapters for everything (Advanced Adapters, google them?) If you still can't get it, get back to me.

Where are your pictures of this truck? I guess I could go look at trackside, but then again, you could post them and save me the trouble.

[ErikShallbetter]

Fmx is junk, you can tell them apart because the fmx has a cast iron center section.

Save your self the hassle and just get a Ford engine trans and transfer case from a wrecking yard.

Either way good luck.

[EQuin]

My trans is a 2WD but I guess I need to find out if it's big block trans or small block trans. I talked to a mechanic today about the C-6 and he said the regular C-6 is just for big blocks and there is another trans called the FMX C-6(FoMoCo experimental) that can work with a big block or a small block. Does that sound right? Anyways, he said a C-6 trans in the shape that mine is in (fresh rebuild with 0 miles on it) is worth around $1000-$1500 depending on if it's the regular C-6 or the FMX C-6. Does that sound about right?

That doesn't sound right at all. I have a 4wd C6 from a 351W (small block) in my backyard right now. Maybe the big block C6 has different/stronger internals than a small block one? I have no idea, but the small block C6 is still called a C6. All I know is that the bellhousings are different between the two, but who knows, maybe the internals are different as well?

[sickrick]

Equin is right.

All c6 trans are basically the same just the bolt patterns are different. You can find c6 transmissions with Small block, Big block, FE block and diesel bolt patterns that I know of. The C6 has the bell housing cast together with the main housing.

There are 2 main c4 transmissions: Big bell housing and small bell housing. Don't confuse the term big bell with big block. big and small in reference to the bell housing only referes to the way/size of mounting the bell housing to the transmission body.

The big bell housings bolt to the trans using a set of bolts outside the front pump, I have only seen this type of trans with the dipstick running into the pan but have been told this is not always true.

The small bell housing is attached with the same bolts that hold the pump on. I have only owned small bell housing trans that have the dipstick into the housing but this may not always be true.

I know this gets confusing but its worth knowing if you are going to be a Ford guy.

If you follow what I wrote above you will see that you can have a; big bell, small block c4.

You can also bolt a small bell to a big bell trans by disregarding the original/outer bolts on the large bell trans and use the pump bolts instead. In this case you could have a small bell on a big bell trans for a small block. Somewhere we have a big bell trans with a small bell housing for a 2.3.

The FMX is not a c6 and shold not be confused with one, the case is cast iron. The Fmx is fine for a all original car or truck but there are not alot of easy to find parts for them are are not worth the hassle. The FMX was available for big and small block engines.

In my opinion there are only 2 performance automatics for a full size truck, the C6 and the turbo 400. All of the other transmissions are just to expensive or weak or both.

The 2 speed powerglide is good for short course if you can get by with only 2 gears.

Bajafand, try asking another mechanic with more ford experience.

[BajaFand]

Thanks alot for your advice and help sickrick, I appreciate it! I do know for a fact that I have a C-6. sickrick, what would you say about the value that the guy told me for the C-6, $1000-$1500. It's a fresh rebuild with 0 miles on it, it looks brand new.

[Big Oly TT]

Go one way or the other, chevy engine and trans or ford engine and trans.

Don't bother with the 700r4, TH400 or c6 both are good.

Its a Ford truck so I reccomend the Ford motor/trans combo..

I have to agree with sickrick. I like chevy and fords, but don't whore the thing if you don't have to. It will be worth more, and sell easier if you left it all Ford. If you go with the th-400 with a Ford engine we will still love you. The other way around............ouch..............my mind won't let me go there.:D

[Big Oly TT]

Very cool Marshall! I wish I had the wheelbase to do the same on my Bronco. What's involved in making it a 6-speed?

You can do it. Gear vendor offers a short and long tail version. You get the short one. It replaces the stock tail housing on the c6 or any other tranmission. they have all the kits. Now you have what ever speed transmission you started with, plus one (the overdrive)! Now, it is a 4-speed. Now, here is the secret...........don't tell anyone, since I am the only one presently racing with one. haha. No, really. You thought that is cool, I just started. Now, you put that "special", custom shifter box deal with everything else I just mentioned.................whala..........6 forward shifting speeds for a c6 trans! There are only a handfull of them out there. Chip Foose has one and the fastest winningest CORR racers use them. And the Herbst spent $250,000 for their undependable, overbuilt, too heavy 6-speed? And I only spent about $3000, plus my $3000 race trans. Call Gear Vendors in Santee or El Cajon? for more info. :cool:

[steveG]

I've looked into the Gear Vendors units a bit and loved everything about them. Especially the gear splitting, that just plain rocks! I've always been surprised at how few there are in the desert. When compared to the amount of money people have in race trucks it seems like such a small expense that can net you so much.

Post pics!

[steveG]

Oh, and Eric, I agree, don't whore the truck out of you don't have to.

[SimonSays]

Do not go with the 700r-4 that was chevys worst tranny they have ever made!!!!! If you want a good tranny go with the th-400 or the c-6 (neither is better then the other) th-400 may be more common not sure.

P.s why you want to put a chevy engine in a Ford, not leagal for any racing (and just rude to the Blue Oval)

[BajaFand]

Chevy engine in the Ford because it was a steal! Atleast it will be, I haven't made the purchase yet, but it's just waiting for me to. The only thing keeping from doing so is seeing if I can pick up a 351 for not much more. A complete Chevy 350 for $300 ready to go or a semi complete 351 for $1000+... If you were raised in a Chevy family which would you choose?

Also, how many '32 Ford coops do you see with Chevy engines in them? ALOT. How many 32 Chevy's do you see with Ford engines in them? Almost none at all.

[ntsqd]

Do not go with the 700r-4 that was chevys worst tranny they have ever made!!!!!
Have to disagree. The early units weren't very good. Neither were the early AOD's. By '89 both OE's had them sorted out. Maybe not as strong as a TH400, but totally undeserving of being called the "worst GM trans ever made."

(and just rude to the Blue Oval)
Agreed.

[sickrick]

You're right the 700r4 is ther 2nd worst transmission gm ever made. The metric th200 is the worst.

[SimonSays]

Have to disagree. The early units weren't very good. Neither were the early AOD's. By '89 both OE's had them sorted out. Maybe not as strong as a TH400, but totally undeserving of being called the "worst GM trans ever made."

Agreed.

Worst GM Trans ever works for me,
My aunt had it in her 'Burban went threw 4 of them in 2years, then she got rid of it.
AOD's in the rangers/explorers suck but the fullsize i haven't seen lots of problems with.

[Sheaco]

I have a '71 Ford F-100 project that I am just starting to get underway. With my F-100 came a brand new looking freshly rebuilt C-6 transmission ready to go with the acception of a torque converter, but no engine. I just bought a Chevy 350 engine for it this weekend. I want to switch out the C-6 for either a Chevy TH-400 or 700r4. My question is: is it worth the hassle switching the Ford trans for a Chevy trans or should I just get an adapter plate to bolt the 350 up to the C-6? Assuming there is an adapter plate for this application? Also, I'm a Chevy/Toyota guy so I don't know the first thing about a C-6. Are they 3-speed or 4? How much could I sell it for? Would it be worth it to trade straight across for a TH-400 or 700r4 of the same condition/quality or would I be getting ripped off if I did that?

BajaFand, what are your plans with this truck? i.e. Race truck,prerunner? usually with most trucks builds, in order to get the out of the hole or get on top of the whoops kind of power most all people use 4:56 gearing or around there. So if your going to be driving mostly on the highway you may want to go with a four speed in order to drop your crusing rpm. We have multiple pre runners with over 500 hp and all have 4 speeds.

[BajaFand]

Well, if I do end up with a Ford engine it will be a class 8 legal prerunner that will be 4-linked. If I still go with the Chevy I will backhalf the frame and tube it. It will mainly be to prerun the races with but I would like to race it in 8 or sportsman when it's done. I don't know what kind of HP I will be getting, but probably nothing special. It will be street legal and see some street use, I just don't know how much. I have had the same thoughts about 3 speed vs. 4 speed. If it will see any pavement at all should I not stick with a 3 speed?

[ntsqd]

snippage.....
AOD's in the rangers/explorers suck
Those are A4LD's or something like that, & typically they do. I've always inferred that the "LD" stood for "light duty." Not the same trans as the AOD.

[wrightracing.net]

I have a gear vender on my motorhome and it is great. I am running a 454 GMC motor with a turbo400.

[scottm]

I'm an old-school chevy hot rodder, and I want to stuff a sbc into everything that moves from lawnmowers to airplanes. Plus I love to watch Ford guys squirm when asked to explain why chevys are so popular, especially in ford vehicles. But I have to agree with everyone here - keep a ford engine in it, as original older vehicles of all kinds are getting rare. You may save a little money with the chevy, but maybe not after everything is accounted for.