Good evening. Thanks in advance for any advice you can offer.
Sadly, our recently purchased EB now has a transmission that is slipping. Not something I wanted to deal with right off the bat but here we are.
Stock 302, C4, 3.50 gearing, 33” tires w 15” alloys, 80/20 highway/off-road use, sea level, flat earther. Like the current gearing span of 3.50s and the look of our 2.5” suspension lift w no body lift. But not completely opposed to 1” body lift if need be.
We actually prefer driving manuals and love their rugged simplicity but bc we’re not positive we’ll keep this EB, hesitant to go through hassle of conversion that might result in lesser appraisal.
Considering options to include rebuilding C4 myself though no experience, shop rebuild, RAT/RAN conversion, new process trans bc of granny gear and/or other options.
Open ended question I realize, but what are your thoughts? Thank you.
OK, here I go...
Everybody knows that I hate automatic transmissions. All of them.
BUT, if I were you, I would rebuild your C4.
Stop wasting money trying to patch it. The instant a C4 starts to slip is the day that you should stop driving it. A master rebuild kit costs about $90.
The only thing wrong with your transmission is that it can't build pressure, because a lip seal behind a piston has failed. Stop trying to find ways to spend more money. There are many, many, early broncos with C4's and 3.50's. You KNOW what's wrong with yours. So you don't need a torque converter, and you don't need a valve body, and you don't need a governor, or a modulator. Don't need bands either. It's the worlds easiest rebuild.
If you take it to a shop, they are going to charge you for a complete rebuild, and replace everything. Including the stuff that doesn't need replacing. That's how they stay in business. If I were building your transmission, and I had to give you a warranty...I would replace everything, and you would pay for it. because I can't afford to do it twice.
But If I owned it, I would yank the C4, pull the valve body and front pump, re-seal the pistons, and run it. I would probably even re-use the ATF at this point.
C4 is a robust transmission, and as simple as an automatic can get. Spend $100 and install the rebuild kit. Then drive it and decide if you like it. Then upgrade if necessary.
Done.