When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
So I'm getting a 390 rebuilt to put into my 1976 F150 and I think it's going to have around 335 HP. The truck is automatic 2 wd. My C6 transmission has slipped a little in the past and I'm thinking I might save myself a headache by just pulling the tranny and get it rebuilt while I'm pulling the motor anyway. I called 6 local transmission shops and got prices from $850-1900. I think I could buy a new one online for around $1300, so I guess the shops quoting me in the 1500-1900 range don't want to do it. One guy seemed like he would like to work on it for me and quoted $850. Another guy that quoted $1200 said he would do the following upgrades: shift kit, kolene steels, pro series kevlar lined intermediate band, larger servo, new torque converter. I think everybody puts in the new torque converter, but I don't really know what the rest of that stuff means. I assume the guy that quoted me $850 is doing a stock rebuild, but I could call him back and ask him to adjust the quote to include certain upgrades if I know what to ask for. What do you guys think?
One thing is you get what you pay for but ...... before you lay down your hard earned cash for a rebuild make sure you know what your getting and find out more about the shop that’s going to do the work for you.
My mechanic does them all the time. He did my turbo400 in my 68 Firebird that has a 550hp engine in it. He did the whole rebuild for $600 (not including the torque converter which I bought a higher stall converter). Tranny is still working like a watch 4 years later.
He did my C6 for about the same amount. I didn’t get a new converter. Mine was working fine. He did put a new shift kit in it for me and readjusted/recalibrated the shift points etc...that tranny was done like 3 years ago now. Again no issues. My truck is a 77 4x4 with a 460 in it.
I’d say normally the price is higher for rebuilds. Again it’s who you know and where you go.
Buying a used tranny....make sure you get a warranty. Buy from a reputable place.
You want me to provide a full list of the basics? I also suggest a R Code servo, I can even give you the full ATSG manual if you want to do it yourself.
Since I don’t have a connection to get it rebuilt for $600 and it looks like it will be about $1200 to get the upgrades, this might be my best bet:
There’s a $50 off coupon and free shipping, so by the time I buy this and a torque converter, it comes out about the same as the rebuild with upgrades option and this is rated for up to 525 hp, Dyno tested, guaranteed, etc. Anybody gone this route?
TCI and B&M are the biggest waste of money, absolute junk products. They ride on a name and false claims, don't expect after sale support either. If you want to order online I would go with Monster as they have gained a good reputation in the racing and performance industry and offer a good value.
R code servo is cool but MAKE SURE and match the strut, or else you might as well take that old case and throw it in the scrap pile because that servo will bust the case. Colleen and her steels do nothing ... yeah nothing for clamping pressure under hi power load/launch. they are a much more heat tolerant component under slippage. Your power level WILL NOT even phase an ordinary C6. The place your upgrade needs to emphasize on is surface area of clamping, now this generates more heat but also outlasts and out clamps any code or any steel. In order to achieve this you need to add more clutches to the stack. This can be done by removing the wave washers, machining your reaction plate, buying thinner reaction plates, or machining the snapring closer to the outside opening of the drum. A ordinary stock borg warner stock clutch/steel pack will tolerate enough clamping power and force to cause broken cases. I have a little stack to prove it. Durability, longevity, and extra torque input are all going to be from more friction/steel stacks. I have torn big block c6 outfits down alleged to be original that had 3 clutches installed in them, in a 1 ton truck. I put 5-6 when I build. This thing in a heavy vehicle is going to like to have a soft 2nd gear. That is you band. Your servo is the band. The band can be changed in the vehicle, called a snap band. you can build a snap band from a regular band. The next place I have seen deterioration in high hp application is in the direct drum.
Now, remember that your c6 likely has 3 pin planets. An upgrade to 6 pin would be just that... an upgrade. I don't see any mention at all of 3 pin vs 6 pin, the standard would be 3 pin but the low gear would be able to affordably get you to 6 pin.
TCI and B&M are the biggest waste of money, absolute junk products. They ride on a name and false claims, don't expect after sale support either. If you want to order online I would go with Monster as they have gained a good reputation in the racing and performance industry and offer a good value.
The Monster C6 starts out at $1199, add $299 for the round one that fits a 390, add $225 for core return shipping or consider it a warranty charge since you can opt not to return the core and just decline the warranty. They also charge $189 for the factory low stall torque converter (rated up to 300 hp) which sounds to me like they suggest the $300 torque converter for my engine. If you choose not to buy the torque converter from them they knock the warranty down to 30 days. I'm not knowledgeable about transmissions, so it's tough for me to really evaluate these options. If I need to research planets and servos, etc to make an informed choice I can do that. Ultimately my goal is to have a reliable transmission in my truck. My current one feels worn out and I'm being told that hooking up a more powerful engine to it is asking for trouble. My brother used to work as a mechanic and now just works on his own vehicles and goes off roading in his truck had good things to say about the TCI, but I'm not 100% sold on that by any means.
and I can't say. I researched in order to spec what I wanted to the builder, and found that I was more than capable to do it myself. 10 years later, I have built more than I can count and fixed even more that malfunctioned. Best of luck to you.
It is hard to say. Without knowing driver expectacions, vehicle weight, tire size, driving conditions, towing expectations, economy requirements, rpm range, traction, and gear ratio. A vacuum modulator can be tuned or swapped to make more difference in performance than almost any other part, but that boils down to vacuum, in order to make that selection a person almost as to get the engine broken in good and tune it from there.
If you exchange it, make sure it has the right tail shaft and the right shifter in it to hook up to your linkage.
Good call. Right now I have a 360 in my truck and I’m swapping in a 390. That is supposed to be a bolt in swap. But when I look up the big block version of the c6 like the picture I posted above, it shows a flat edge at the top. But my current transmission looks more rounded, so that is confusing me:
Is the flat part on the bottom? I never took pictures from underneath.
Btw, I don’t know if the 360 is original to this truck. It seems odd to me that when I pull the oil plug, the oil dumps all over the cross member and gets everywhere, including on the exhaust y-pipe.
gxqZxoCvEcQAvD_BwE
