Austin Vert Seeks Pro Tech Help on Transmissions

[Austin Vert]

Hi Folks,

I seek professional tech help and advice to do with my C4 Auto transmission.

To start with, i am one of those guys that was never really switched on or very knowledgeable about the mechanical side to cars. I do know the basics. As a lot of Forum members would know, my major strength lies in Spray Painting and panel beating.That has been my life career. I ignored jumping in and leaning about mechanics in great detail throughout my life by choice, and i guess looking back, i have paid somewhat of a price for that.

That said and due to my ignorance, i am now in a position where it would seem my ignorance has let me down again, and i need some good professional help to help solve my problem. Before i jump in, let me say that i have a first class, professional transmission specialist that lives close by. He is honest, trustworthy, and been in business since 1980.  I have given him my business all these years with my transmission needs. He will ultimately guide me as to what he thinks will be the best approach for me to take. You never stop learning, and that's why i am approaching the Forum for pro tech advice, because your feedback will help educate me and help me also make the best decision as well.

OK, my short story. My 1973 Mustang has been babied all it's life and is in great condition all 'round. I bought it with a factory original untouched 302 Windsor and a C4 tranny. The tranny has never played up and i have kept it serviced well over the years. Two or three years ago,  i decided to rebuild my engine, chasing more power. It got totally rebuilt with a 347 stroker kit. The only original part kept on the rebuild was the numbers matching block. After the rebuild, and with the engine out of the car, the Dyno testing showed it was putting out 400ft lbs of torque and 407 Ponies at the flywheel. Ok, and that's that. What no one ever told me, and what i never knew or took into account, was how this increase in power was going to effect my tranny. I did install a 2.5 stall new torque converter, on advice taken. I thought that based on my limited knowledge i knew, that the C4 stock tranny would handle the extra power. NO.

Now i learn, based on new online investigation, that the chances of my stock tranny survival is slim. Last week and for the first time, my tranny started to slip between second and third gears when i was accelerating fairly hard up a long steep road. My trans go to man, thought it might be a modulator issue. He has replaced the original one, but that has not helped. He now tells me that i may be looking at a complete rebuild because of the age thing, plus upgrading to meet the new engine power output. I have looked around online, and it seems you can buy performance upgrade kits (like Monster Performance brand) that will work for a performance upgrade. By the way, i am one of those drivers that don't do burnouts, drags, donuts , wheel spins etc. So what am i looking at here guys. My trans go to guy has quoted me a ball park figure of around $3,000 to $4,000 Australian dollars to basically rebuild the trans. (labor and materials)

I wonder if i can get out of jail and upgrade the trans for cheaper money.

So that's it guys. Any help and good advice would be greatly appreciated from me.

Thanks,

Greg. :help:

 

[Bentworker]

Are you going to do the work or is your transmission guy?  Considering a catalog unit from a remote shop?

Personally I would shy away from Monster.

In the transmission world Sonnax is well regarded.  They make torque converter kits (for custom converter shops) and they make a trick servo for a C4.

Some good Raybestos or alto frictions, a good shift kit to raise pressures and you should be good to go.

Jay at Broader really knows the C4.  He built up my FMX and I have not managed to grenade it yet.  If you go with a “catalog” unit I would suggest Jay.

https://broaderperformance.com/product/forward-clutch-upgrade-kit-red-frictions/

https://transpartswarehouse.com/catalogsearch/result/?cat=&q=C4

 

[Sheriff41]

Did you adjust the modulator?  There is a screw inside the hose nipple that allows you to fine tune the up shift.  Turn it clockwise to firm up the shift.  I would try only one turn at a time and no more than four turns total.  If that doesn't have any affect then you have more serious problems. 

 

[Austin Vert]

Hi Bentworker,

Thanks for your feedback. I will not be doing any work myself as my knowledge base is very limited here. My trans guy will be taking care of everything.

I will look into your recommendations in more detail. Thanks again for your advice.

Hi Sheriff,

He has adjusted the mod once, and wants to try adjusting it again. As you say if that fails, i'm toast. Thanks for your advice.

Greg. :classic_rolleyes:

 

[71ProjectJunk]

I just looked the the $3-4,000 AUD dollars ($2,200-$3,000 USD) and though that was a ton of money for a mild performance rebuild that does not include a torque converter. I started looking to see what an already built, ready to run performance trans was going for and they are not cheap nowadays. I have been out of this for so long that prices just seem unreal. I had a friend of mine, back in the mid-90's that used to rebuild my transmissions, I would buy all the parts, and give him the transmission, and he would rebuild it for me for $125, and he was really good. I guess those days are long gone. I would assume that the price he is quoting you is with him doing all the work of removing and installing the transmission, if not you need to get someone else. If I were you I would ask him how much he would charge you in labor to build the trans if you remove it, clean the outside, and bring him all the parts. Performance transmission rebuild kits for the C4 seem to be hovering around $300 USD, and if he does not find any parts that he needs to change internally, that should be about all you spend on parts as you have a new converter, plus whatever you spend on oil. You can always add a deeper pan or whatnot, but it is not necessary. A good transmission guy can do a transmission in 2-3 hours, that is what my buddy used to take doing mine. No reason why he should charge you a couple of grand for a couple of hours work.

What I would add is an external transmission cooler (hooked inline with the stock radiator cooling), you really need one when running a higher than stock stall speed converter. High stall converters create a ton of heat, and if you ask any transmission guy, they will tell you that heat is the number 1 killer of transmissions. 

 

[Austin Vert]

Hi 71 Project,

Thanks for your feedback.

In Australia, labor costs are high with mechanical businesses operating under professional business standings.(around $90.00 to $180.00 per hour Australian) To save money, your only hope is to deal with a back yarder, or a friend of a friend that knows a friend. I have gone down that road before and got burned badly, so that option would be out for me.You mention that basically, rebuild kits are not too expensive, (around the $300.00 mark) and labor times comes in around about 2-3 hours. Does that include remove and refit time as well? I am not skilled enough to r&r the tranny myself. That would have to be part of the overall cost. His ball park figure quote includes removing and refitting the trans. . (BTW, how long does it take to remove and refit a C4 trans in a '73 Mustang?)

 If what you are saying is so, it would pay me to get a couple of separate quotes from other companies to verify what i should be getting charged for a job like this. I have not yet discussed with my go to transmission man, the prospect of using an upgrade kit, and how that would reflect on overall price. I had intended to do this in the upcoming week. Regards the trans cooling, i recently purchased a good quality trans cooler with fan, that sits in front of my main radiator. When i installed this fan, i disconnected the hook up to the main radiator.  My go to man, last week advised me to reconnect the main radiator trans connections up again, and run the trans cooler in series link up with the main radiator as well, for maximum cooling effect. It sounded like a good idea to me to help keep operating heat temps down. This will, be done. Lastly, my transmission guy, enjoys a State wide/Australia wide positive reputation as one of the best reliable operators around. For many decades he has been building world class drag racing transmissions for many well known clients in the racing field. I guess getting other quotes will verify if he overcharges or not. I have always been under the belief that he doesn't.

Cheers,

Greg. :classic_unsure:

 

[Hemikiller]

R&R for a C4 would be about two hours each way, and IMO that would be on the high side. Aftermarket parts may add to the time, such as if a header that needs to be removed to drop the transmission. 

If he's doing the whole job and all you do is drop the car off and write the check, then his price seems fair as along as it's not a completely "stock" rebuild. I'd expect some higher capacity performance clutches and an aftermarket servo, and a shift reprogramming kit. I'd also insist on all new bushings throughout, and a new reverse band and servo, as those tend to get re-used, but are now 50 years old. I would discuss to find out exactly what he plans to do. 

If your car still has it's original PEE-xx tagged transmission, then it already has good parts in it. It should have a 5 friction forward drum and a 4 friction reverse. At 400hp, you don't need the big dollar billet drums. 

 

[Bill73Ragtop]

Did changing over to an AOD setup figure in your discussions / research?  For what it will cost to do the C4 rebuild you are talking about,  how would  AOD prices in Aus compare?

 

[Austin Vert]

Hi Hemikiller,

Thanks for your feedback. OK, so if remove and refit takes around 5hours say, and assuming he has all the parts needed to reco the trans at his disposal,and ready to go,  then how many hours do we factor in to work on the trans on the workbench? Lets say he's charging me $120.00 per hour in labor costs, then that means around $600.00 for r&r, plus $++++  for however long it takes to work on the tranny upgrade on the workbench, plus the parts bill. You seem to think that his $3,000 to $4,000 quote is fair providing he uses the upgrade performance parts needed. Thanks also for your parts tech advice. I can put these things to him, to achieve the best performance and cost outcome for me.

Hi there Bill,

Regards AOD setup - no, this has not been discussed with my transmission guy at all. It can be raised. I myself know nothing about the AOD thing at all, sorry. Sounds like another learning curve in my soggy saga. Thanks for raising it with me.

Greg. :classic_ohmy:

 

[Bentworker]

I think you should ask your transmission builder for a buikd sheet to go along with that quote.  Trying to compare costs from shop to shop without one is like comparing apples to oranges.

One shop might slap in the cheapest frictions and steels they can find, rinse out the torque converter and fill it with Walmart ATF.

Next shop might use the best frictions and steels money can buy, do trick upgrades to add clutches to the clutch packs, install a shift kit, bigger servos, stronger hard parts, quality fluid, cut apart your converter and braze the fins, or build you a new converter from a kit, maybe even slap on a cool pan.

By all means don’t get taken advantage of, but spending a few grand on a transmission isn’t a bad investment.

 

[Austin Vert]

Thanks again Bent,

I'll bare all that in mind.

Greg. :thumb:

 

[Hemikiller]

Bent has some very valid suggestions, a spec'd out build sheet of what they will be quoting you is a must. 

If you're trying to analyze his hourly rate on a trans rebuild, you're going to be getting into the flat rate grey area. He may be able to rebuild a C4 to spec in two hours, or maybe it's ten, maybe it's twenty. It depends on his familiarity with them, and what damage he finds. The bushings can be time consuming to R&R, and any parts he has to refurbish add to his time. Going through a valve body takes time, as you need to ensure each valve moves freely under it's own weight. He also has to stand behind that job, so there is always some padding put in for the odd rebuild that just blows up a week later. 

Back in the day, I worked at a transmission shop doing R&R and general repairs. I could have an automatic out of a typical American car or truck in under an hour as long as the bolts weren't rust welded. Exhaust systems were always the big unknown. Our rebuilder could pretty much do any 3 speed auto in under four hours. Our biggest delay was always parts, as the owner was a cheap f&ck and wouldn't stock even the most common rebuild kits and converters. We were always removing, pushing the cars outside, then waiting two days for parts and pushing them back in. It was a PITA and a huge waste of time. 

 

[Austin Vert]

Hi again Hemi,

Thanks for your updated info. Lot of good feedback and advice there. I will make sure i get a detailed written breakdown as to all replacement parts used,parts and labor costings etc. My rebuilder should provide a written guarantee to the job as well.I would think two years be a fair time - i will see.

Interesting feedback on your own experience working in that trade or business. Sounds like you had a tight arse boss that did not want to spend monies. I bet you also worked pretty hard, and didn't get paid much of a wage. I have worked for bosses like that in my trade too.

Thanks,

Greg. :classic_smile:

 

[71ProjectJunk]

If you can't do any of the work yourself, then you are probably stuck at the quote you were given. Transmissions rebuilds are one of the most profitable parts of the automotive world, along with brake jobs. A good, experienced transmission guy with a properly setup shop and tools can remove, rebuild and install a transmission in half a day, and there is not that much in parts, unless stuff is just damaged inside the transmission. If they know what they are doing, they do not buy a B&M, TCI, Turbo Action or any of those "performance" rebuild kits we would buy. They get the individual components that are on those kits from Raybestos and others, and end up paying half of what a brand name kit costs, as all those kits are is repackaged Raybestos or other brand name components in there, the brand name guys make very few of the parts in those kits, they just repackage the stuff anyone can buy and then mark them up. 

Here is a video of a C4 transmission rebuild by a professional. From when the transmission is brought in completely assembled to the time the transmission is finished is just over 1 hour. There are very few parts of the video that are fast "fast forwarded" or edited for time, it is mostly in real time. Only thing I can see that they cut out is the cleaning of the parts and the case, which can take 15-20 minutes. They also talk a lot on the video so there is some time lost as to how fast a tech would take to assemble one of these transmissions:



At one time in the early 2000's I had an auto repair shop, transmissions were like brake jobs, extremely profitable. You would charge, back then about $300 for a simple brake job, that would take an a little over hour to do and had maybe $20-$30 in parts. We had an on car brake rotor cutting machine, you would take one front caliper with brake pads off, and immediately put the brake cutting machine on it, then get to disassembling the other other side, by the time the other side was disassembled you could move the rotor cutting machine to to that side as the first side was finished. You then got to the rear, took off the drums and machined them, brake cleaned the rear brakes, if the brake shoes needed to be replaced that was additional, and it was quite a bit more. You then installed the calipers with new pads, and put the rotors on and adjusted the shoes. We loved brake jobs... Lets say that all in all, including getting the car in and out of the shop you had 2 hours, the tech that does the job got paid $20-$25 ($20-25 an hour depending on what tech you used), and you had $20 in pads. I would pull the cars in and out a deal with the customer. So, out of the $300 the shop profited somewhere in the $250-$260 range for 2 hours worth of total time. If you could do this all day long one tech would make you $1000 a day. Transmission are even better, you charge a couple thousand dollars + and have a couple hundred dollars in parts, and to exaggerate, maybe a couple hundred more in hours you pay the tech... Big transmission shops that get a bunch of transmission a day are like being able to print your own money.