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Transmission Trouble...HELP [message #277839] Thu, 14 May 2015 16:55 Go to next message
Bob S. is currently offline  Bob S.   United States
Messages: 143
Registered: October 2012
Location: Rapid City, SD
Karma: 2
Senior Member
I had a shop change out the shocks on my 78 Royale and when I picked it up I drove about 3 blocks and the tranny felt like it went into neutral. I pulled over and it moved again, ran up to about 35mph in first gear then went back into neutral. I had reverse and first gear.
I took it back to my mechanic and applied the knowledge I've learned since reading this forum. I ordered a new governor gear from Jim K. and told the mechanic to install it. When he took the old one out, it looked ok. I had them replace it anyway. He reassembled it today and it is still acting the same way. The modulator is not leaking and appears to be ok. My question: Is there anything else I should look at before condemning the transmission? Any help and encouragement will be greatly appreciated.


Bob and Pam Schilling Rapid City, SD "78 Royale
Re: [GMCnet] Transmission Trouble...HELP [message #277840 is a reply to message #277839] Thu, 14 May 2015 17:04 Go to previous messageGo to next message
bdub is currently offline  bdub   United States
Messages: 1578
Registered: February 2004
Location: Central Texas
Karma: 5
Senior Member

Look for a vacuum line that got knocked off the modulator valve.

bdub

-----Original Message-----
From: Gmclist On Behalf Of Bob Schilling
Sent: Thursday, May 14, 2015 4:56 PM

I had a shop change out the shocks on my 78 Royale and when I picked it up I
drove about 3 blocks and the tranny felt like it went into neutral. I pulled
over and it moved again, ran up to about 35mph in first gear then went back
into neutral. I had reverse and first gear.
I took it back to my mechanic and applied the knowledge I've learned since
reading this forum. I ordered a new governor gear from Jim K. and told the
mechanic to install it. When he took the old one out, it looked ok. I had
them replace it anyway. He reassembled it today and it is still acting the
same way. The modulator is not leaking and appears to be ok. My question: Is
there anything else I should look at before condemning the transmission?
Any help and encouragement will be greatly appreciated.


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bdub
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Re: Transmission Trouble...HELP [message #277881 is a reply to message #277839] Fri, 15 May 2015 16:16 Go to previous messageGo to next message
KB is currently offline  KB   United States
Messages: 1262
Registered: September 2009
Karma: 0
Senior Member
also check the shift linkage. We had a similar problem recently, and it appears to have simply been the linkage.
Thought maybe a plugged up vacuum modulator line, but I took that off, cleaned it, and made sure it was clear.
I imagined that fixed it, but then it did it again. On a whim tried pulling the shift lever to S then back to D and it went into gear.

I've now readjusted the linkage per the manual and (so far) it's behaving. The adjustment is just a bolt/clamp/bar arrangement
on the side of the tranny that links up to the shift lever in the dash, but there are detents in both the tranny and the
steering column that will fight each other if not properly adjusted.

May or may not be your problem, but an easy thing to try.

Karen
1975 26'



Bob S. wrote on Thu, 14 May 2015 14:55
I had a shop change out the shocks on my 78 Royale and when I picked it up I drove about 3 blocks and the tranny felt like it went into neutral. I pulled over and it moved again, ran up to about 35mph in first gear then went back into neutral. I had reverse and first gear.
I took it back to my mechanic and applied the knowledge I've learned since reading this forum. I ordered a new governor gear from Jim K. and told the mechanic to install it. When he took the old one out, it looked ok. I had them replace it anyway. He reassembled it today and it is still acting the same way. The modulator is not leaking and appears to be ok. My question: Is there anything else I should look at before condemning the transmission? Any help and encouragement will be greatly appreciated.

Re: Transmission Trouble...HELP [message #277887 is a reply to message #277881] Fri, 15 May 2015 17:33 Go to previous messageGo to next message
Bob S. is currently offline  Bob S.   United States
Messages: 143
Registered: October 2012
Location: Rapid City, SD
Karma: 2
Senior Member
Thank you for your help. We are checking the vacuum then we'll check the linkage adjustment. I'm keeping my fingers crossed that it's nothing serious. Thanks Again, Bob

Bob and Pam Schilling Rapid City, SD "78 Royale
Re: Transmission Trouble...HELP [message #277901 is a reply to message #277839] Fri, 15 May 2015 22:06 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
Senior Member
RULE 1. Check the fluid level. Warm, in oark, engine running. That said they vould have pinched or dented a hard vac line.




John Lebetski
Woodstock, IL
77 Eleganza II
Re: Transmission Trouble...HELP [message #277944 is a reply to message #277839] Sat, 16 May 2015 23:09 Go to previous message
Bob de Kruyff   United States
Messages: 4260
Registered: January 2004
Location: Chandler, AZ
Karma: 1
Senior Member
Bob S. wrote on Thu, 14 May 2015 15:55
I had a shop change out the shocks on my 78 Royale and when I picked it up I drove about 3 blocks and the tranny felt like it went into neutral. I pulled over and it moved again, ran up to about 35mph in first gear then went back into neutral. I had reverse and first gear.
I took it back to my mechanic and applied the knowledge I've learned since reading this forum. I ordered a new governor gear from Jim K. and told the mechanic to install it. When he took the old one out, it looked ok. I had them replace it anyway. He reassembled it today and it is still acting the same way. The modulator is not leaking and appears to be ok. My question: Is there anything else I should look at before condemning the transmission? Any help and encouragement will be greatly appreciated.

I don't think the modulator nor the governor can cause this. Hopefully it is low fluid .


Bob de Kruyff
78 Eleganza
Chandler, AZ
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