Transmission slipping in and out of gear
#1
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Certified GM nut
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Transmission slipping in and out of gear
I thought I was driving on ice: I hit the gas, heard the engine rev, but the car waited about half a second before moving. After it happened on a clean road, I noticed the tach went up, but not the speedometer. Certainly seems like my transmission is slipping out of gear.
Naturally, I've observed the heck out of it, trying to figure out exactly what component is failing:
I've looked at used cars near me and was not impressed, so I've decided to proceed with the repair. Should I start searching junkyards, or would it be cheaper to get this one rebuilt? (At minimum, I know it needs a torque converter and the updated valve body, plus the standard rebuild parts, and maybe a shift kit and secondary cooler.)
Naturally, I've observed the heck out of it, trying to figure out exactly what component is failing:
- I've lived with the typical 4T60-E lockup issues for a couple years, with P1870'* only on the hottest summer days.
- It never slips while driving at a steady speed.
- It slips most often about two seconds after taking off from a stop.
- Shifts haven't gotten any harder or softer.
- Temperature doesn't seem to matter much.
- Slips in 1, 2, 3, and Drive, but never in Reverse.
- My scan tool says the TPS is working, but it can't check transmission sensors like line pressure.
- Vacuum lines to the modulator look great.
- The fluid is brown and reeks. It was the color of merlot and smelled okay when I checked it last (just after Thanksgiving), so it must have gone downhill over the holidays.
I've looked at used cars near me and was not impressed, so I've decided to proceed with the repair. Should I start searching junkyards, or would it be cheaper to get this one rebuilt? (At minimum, I know it needs a torque converter and the updated valve body, plus the standard rebuild parts, and maybe a shift kit and secondary cooler.)
#2
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Expert Gearhead
Which way to go is your call. If you go for JY. look around and try to find one with a SERTA sticker on it. That'* the GM factory remaned sticker. This way you know it'* been rebuilt at some point.
It'* not too bad to toss one in. Figure a day if I'm on the job. All your engine to trans bolts won't fight. We already know that fact. BTW it'* a perfect time to replace battery cables, we'll have to unhook ...uh one.
(Justin..I think he likes the cam)
It'* not too bad to toss one in. Figure a day if I'm on the job. All your engine to trans bolts won't fight. We already know that fact. BTW it'* a perfect time to replace battery cables, we'll have to unhook ...uh one.
(Justin..I think he likes the cam)
#3
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Certified GM nut
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Well, both options are good. If I swap, I'm bumping up to the 3.06 gearing. If I rebuild, I'm dropping in the GM Forum and 4T60Ejr shift kits, and maybe a higher-stall torque converter.
Yes, battery cables, wheel hubs, and maybe center sway bushings will be replaced. (I'll be brainstorming.) This tranny was nice enough to wait until I became financially stable before being eaten alive by the cam.
Yes, battery cables, wheel hubs, and maybe center sway bushings will be replaced. (I'll be brainstorming.) This tranny was nice enough to wait until I became financially stable before being eaten alive by the cam.
#4
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Seems like I'm down about a quart or so on the dipstick. I took a shovel to my usual parking space and found a little reddish-brown patch of snow a couple layers down. I'll fill it back up with some Lucas Stop-Slip (or whatever it'* called) and see if that gets me until spring.
#6
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Not yet. I bought the car with two consecutive pan bolts missing (which I didn't notice until years later), so I'd wager it'* from there. I'll find out soon enough.
#7
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Join Date: Mar 2010
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From my experience with these cars the trans pans leak on these cars pretty frequently..maybe it would be wise to drop the trans pan, install a new filter, and put a gasket on, you never know it may help your shifting issues as well
#9
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Actually Justin..the 60 should be fine. Afterall they did use them for a number of years on teh S1 Sc motors and then in 96 on the S2 Sc. Majory improvements from 60 to 65 were pump not caviating at higher rpm and the electronic shift modulation etc.
Colin.. look for the leak, fix the leak.
Mike..that'* kinda odd. I hardly ever see a pan leak with the stock gasket and proper torque etc.
Colin.. look for the leak, fix the leak.
Mike..that'* kinda odd. I hardly ever see a pan leak with the stock gasket and proper torque etc.
#10
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Sure enough, she was just thirsty. I gave her a bottle of Lucas and topped off with fresh Dexron III. Didn't help the leak one bit, but it'* back to its old self and staying in gear.
I've got a spare gasket at home, so now I just need a clear patch of pavement to drop the pan. (I've been itching to try out my new jack and stands anyway.)
I've got a spare gasket at home, so now I just need a clear patch of pavement to drop the pan. (I've been itching to try out my new jack and stands anyway.)