I need to do something about the sloppy, early part throttle shifts in my TH400. As I stated, it just kinda slides through upshifts very sloppily and early (at a low RPM). Does this sound like a potential vacuum modulator adjustment, or other issue. I just recently bought the car but I know from some paperwork that the car has only been driven 1800 miles in the last 8 years so I am wondering if the governor or some valving could be hanging up from sitting for long periods. I'm not a trans guru at all, so any wisdom would be appreciated. BTW, the trans is original to the car so it's not some mystery trans out of who knows what. And it was supposedly "rebuilt" along with the engine around 2000-2003-ish or so. I really haven't put in many miles behind the wheel of this car, so I don't have a great feel for it, and haven't played around with it much. I really don't want to drive it much with the trans shifting this way, seems like it would be hard on the clutches.
Aww c'mon, it's just "well aged". Yea I know, that's a no brainer. Damn, guess I'll have to get the floor jack out.
I'm pretty good at forgetting the simple stuff first, but I do think it's a good idea to do a filter change, and you get to see the stuff in the pan, too. I'd do all the fluids on an older car that's unknown, including differential, and I know you probably don't want to hear it, but I'd bleed through new brake fluid to all four corners too. Devon
I hear ya on that one. I can recall tracing wires, testing components, and pulling my hair out only to find out later that I should have checked the fuse first.ou: I agree on the fluid changes too, and I would thoroughly go through the car...if it wasn't for sale. The fact that it's leaving (hopefully) doesn't make me too eager to dig into a bunch of things. But I will look into the areas where I think there is something wrong since I do have a conscience. The other 70 GS455 sitting out back of my garage will receive "the works" as it is torn apart.
Serviced the trans last night, and played with the modulator. I got it to give part throttle shift at a higher RPM, but they are not as firm as I would like. As I stated though this car is for sale and as such I don't really have a lot of interest in fine tuning so I guess I can deal with the lack of shift firmness.
Is it an adjustable modulator? If so than tighten up the screw to firm up the shifts. I know on mine clockwise (righty tighty) gives it firmer shifts. It takes a full rotation to be really noticable though.
Odd. I know on mine the firmness is controlled by tightening the screw. With that said a full turn only made it firm enough so that I can tell what gear I'm in if I pay attention. I was also planning on going another half to full turn to see if it made it shift any firmer.
I am by no means an expert... But sloppy shifts that happen too soon could be the result of some former owner putting in a cheapy shift kit, or putting one in improperly. o No:
Well, I was able to get the shift points where I would like them to be by simply adjusting the modulator. And I may install a shift kit from B&M or something like that if the car doesn't sell soon. They are very simple to install and have worked well in the past for me.
