BrainDamage
07-02-2005, 11:07 AM
I drove an auto '98 12V truck the other night with 180k miles and while not an expert on these trucks, it seems to have some tranny problems. But perhaps some of it is normal behavior. Other than the tranny it had some other issues (not the engine), but I knew and understood them and right now, I am just trying to figure out what, if anything to offer for it.
First, it wouldn't shift out of first with my foot to the floor. Anyone know about this? It would just stay at about 2700 as long as I kept it to the mat. It did shift after I let off some, but that didn't seem right to me. Maybe it is, someone in the general discussion said it might be.
Second, the truck would jerk while cruising at say 30 or 40 mph. Almost like it had a miss, but the engine didn't sound like it was cutting out. Just a strange bucking. I didn't drive it far enough to get a good feel for exactly when/how it would do it. I'm not even sure which gear it was in at the time. I'm thinking 3rd or 4th.
Third, it seemed to go into gear pretty abruptly when shifting out of park. Maybe this is normal, and I am just used to the gassers, but it seemed like it was more of a bump than I would expect.
It also seemed to make a huge rpm drop in 4th out on the road around 60 mph. Maybe this is just standard lockup behavior, so how far do the rpms usually come down when lockup occurs??
Anyway, I am a definitely ignorant about the CTDs so I thought someone here might have some good input. Maybe the tranny?? Or maybe a converter thing?? Anyone?
Also are the 1998 12V trannies computer controlled or not?
Thanks for steering a newbie in the right direction.
First, it wouldn't shift out of first with my foot to the floor. Anyone know about this? It would just stay at about 2700 as long as I kept it to the mat. It did shift after I let off some, but that didn't seem right to me. Maybe it is, someone in the general discussion said it might be.
Second, the truck would jerk while cruising at say 30 or 40 mph. Almost like it had a miss, but the engine didn't sound like it was cutting out. Just a strange bucking. I didn't drive it far enough to get a good feel for exactly when/how it would do it. I'm not even sure which gear it was in at the time. I'm thinking 3rd or 4th.
Third, it seemed to go into gear pretty abruptly when shifting out of park. Maybe this is normal, and I am just used to the gassers, but it seemed like it was more of a bump than I would expect.
It also seemed to make a huge rpm drop in 4th out on the road around 60 mph. Maybe this is just standard lockup behavior, so how far do the rpms usually come down when lockup occurs??
Anyway, I am a definitely ignorant about the CTDs so I thought someone here might have some good input. Maybe the tranny?? Or maybe a converter thing?? Anyone?
Also are the 1998 12V trannies computer controlled or not?
Thanks for steering a newbie in the right direction.