My 1990's 348tb is starting to get too me. After 3 years of worry-free road and track driving (not really racing) it now needs some TLC. After some wheel bearing, clutch and timing-belt issues the gearbox is gently whistling for attention. In 3th and 4th it its producing more of a singing sound than in all other gears, and it is worse when the oil is hot. Not so much noise as in leave-it-on-the-shoulder-and-go-get-the-trailer, more like; cancel the next trackday I have tracked down a spare gearbox and currently counting I am counting my option. My best option is dropping the original box and fixing it my self. Come on, a gearbox. How hard can it be? Sending it of to a specialist might be a good plan.. Dropping the fresh(?)-one is the chicken-out solution. My biggest consurn is the fact I can not find any "how-to's" on rebuilding the gearbox. Can anyone help me out with some does and don'ts? Regards. Ben.
It is generally within a serious DIY skill set to rebuild a gear box, even a 348. The work however typically requires some special tools that you just have to make up as you go along. The ability to weld and having a welder are likely very beneficial in that regard. In the 348 / 355 space, the acknowledged DIY experts are FBB and Plugzit in Southern California and the remaining Stooge Ernie now in the heartland of America. But, shipping your gear box from Holland seems an expensive option. If I were you, I would take out the old gear box, disassemble it with the help of the stooges, and use the parts from the other gear box to put together a complete working one. After all unless the spare gear box comes with a warranty, who knows what is in it. The true chicken out option is to take it to a professional ... and for a DIY like me, that is just an insult to my toolbox.
Have you done a gear oil change. I had a noisy gearbox on a 996, did a change and slightly overfilled, problem solved. Granted, mine was a bit under filled to start with. Just saying so you can look at the cheaper options first.
Thanx for the replays. Swepco does wonders for Porsches! I too overfilled it a bit as an experiment, and the sounds in 2th are gone. However the whine in 4th is still there... I tracked down a completely rebuild box, but didn't buy yet because, like yellowcab, I want to do it myself... For a coming trip to the Nurnburg-ring I'm considering putting in FinGear, a teflon additive for gearboxes. I've had some great temporary results with other cars. Any thoughts on FinGear? Regards. Ben.
Here you go Ben. These are the instructions for removing the transmission. http://www.ferrarichat.com/forum/348-355/124766-348-transmission-removal.html I forget who it was was but, they figured out that you only have to move the parking brake cable out from under the transmission. He left it hooked up and pushed in down and out of the way under the engine block. There are other threads about removing the transmission/gearbox you just have to search.
Ernie, Thanx for the replay. ...but removing the box does not look like a problem. Its more the work that comes after the removal... I could use some help in rebuilding the insides of the box. Are there any how-to's on that matter? Regards, Ben.
Ben the work shop manual for my 355 goes into a lot of detail on gearbox repair. Unfortunately their seems to be a lot of special tools required. I will be rebuilding mine this fall but not sure if I am going to DIY or maybe whatch a pro do it. It kinda scares me with all the tolerances. If an obviouse part is damaged and I just need to replace it then I might do it myself.
Ben, Unfortunately there aren't any DIY threads for the actual rebuild for the 348 transmission. There are threads of us discussing it, with pictures in different areas where guys were having issues, but no step by step procedure. However this your chance to be the first to post a step by step, do-it-yourself thread, with pictures! It's too bad you aren't over here because we could have taken it out, headed over to fatbillybob's, and had another Stooge gearbox rebuild party.
Ernie, I was looking for an excuse to go to the states.... You bring the tools, I bring the beers? Fun aside, if the shipping-costs were acceptable and the "lost-in-the-mail" horror stories weren't so common, I would be very greatfull the get the full stooge-treatment! Can I lean on you expertice if I get lost in gears? Regards. Ben. Holland
I don't have a problem answering questions, and will be glad to offer help with what I know. Don't forget to hit up fatbillybob, as he has way more experience than I do with rebuilding the gearbox. Just take your time and don't rush anything. Take plenty of pictures and be sure to methodically organize the parts as you remove them.
Yeah, Ben, it isn't rocket science, but it does require patience and organization. Also a BFH. Think about it this way: Three stooges with tools and a gearbox. What could go wrong?
