Can someone help me!?

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OLDMIL21
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  • 1 POST
I drive a 1999 Monte Carlo with 69,000 miles on it. Recently, my car started to "slip" right around 45-50 mph where it shifts into overdrive. It feels like when you spin your wheels on ice and then catch some solid ground off and on. Once you get above this speed everything is fine and it also doesn't do it until you reach this speed. If you accelerate with the car in Drive instead of Overdrive, the problem doesn't occur either. I changed the transmission fluid which was very clean, nice and red without any metal in the bottom of the pan.
What could be causing this to happen?
Jan 10, 2006 at 2:43 AM

What to check next

Diagnostic guidance. Suggested checks and possible repairs are separate from the owner's reported results.

Have transmission codes and operating data checked while reproducing the symptom safely. Ask the technician to identify whether it occurs during a gear change or converter-clutch operation before authorizing repairs.

Guidance references and applicability

Source: This question and its visible discussion. Owner reports are distinguished from other participants' experiences. Follow-up guidance is not a confirmed diagnosis.

Read the replies · Discussion summary and reported outcome

AI-ASSISTED GUIDANCE · REVIEWED BY 2CARPROS
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2CARPRO JACK
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  • 11,533 POSTS
slipping going into OD isnt good. You might want to take it to a reputable trans shop and have it scanned
Jan 10, 2006 at 4:13 AM
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BOOMER2782
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  • 22 POSTS
Sounds like an upshift solenoid in the transmission.
Feb 14, 2006 at 4:33 AM
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KENVCR
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  • 105 POSTS
2carjack has the correct idea. Go to a reputable shop. Your overdrive is shot, but the D 1 2 are still ok. However in order to repair this the whole tranny must be rebuilt.
A cheaper alternative is to look for a used tranny from a salvage yard with a 90ish day warranty. Rebuilt can cost about 1000. Is this car worth it to you??? Plan on getting rid of car soon? Small auto shops can re/re this job usually about 4 to 6 hours if you go the used route.
Feb 15, 2006 at 5:08 PM
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Suggested Repair

Have a reputable transmission shop scan the vehicle for the overdrive slip before replacing parts. Do not assume a solenoid, rebuild, or used transmission is required until diagnostics confirm the cause.

Conversation Summary

A 1999 Monte Carlo with 69,000 miles slips around 45-50 mph when shifting into overdrive, but runs normally above that speed and does not slip when driven in Drive. The transmission fluid was clean and red with no metal in the pan. The expert said slipping into overdrive is serious and recommended a scan at a reputable transmission shop. Other participants suggested an upshift solenoid or a failed overdrive unit requiring a rebuild or used transmission, but no cause was confirmed.

Discussion summary

Can someone help me!?

A 1999 Monte Carlo reportedly slipped around 45 to 50 mph in overdrive but behaved differently in Drive. Replies proposed a solenoid fault or rebuilding the transmission.

Reported outcome: No diagnostic findings or successful repair were reported.

The symptoms and reported fluid condition did not establish a failed solenoid or the need for a rebuild. The quoted repair price was not a verified estimate for this vehicle.

Read the original discussion

AI-ASSISTED SUMMARY · REVIEWED BY 2CARPROS
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