|
Register or Log In To remove these advertisements. |
|
|
|
|||||||
 |
|
|
Thread Tools | Display Modes |
|
|
03-15-2014, 03:00 PM
|
#1 |
|
18 Till I Die
Join Date: Mar 2005
Location: Alberta, Canada
Posts: 1,522
|
Can a tranny knock like an engine on start-up?
87 Silverado 350/700R4. Every morning when I go to work something is knocking like an engine rod knock. Thats exactly what it sounds like and then after about 5 seconds its gone and doesn't return till next morning on first start-up. I thought ok drive it till it craters then drop in a new crate engine. But it wont die. 2 years and counting. If it was a rod bearing it would of packed it in long ago? I'm now starting to think its the tranny?. Its really hard to hear where its coming from, but its loud. I have a vibration as well that has always been there since I bought it. I believe its the torque converter so Im thinking about getting the tranny rebuilt and see if thats it. They did have problems with vibrations due to torque converters back in the 80's..
__________________
2011 GMC Acadia 1969 GMC BBC LS7 2007 GMC Crew Duramax 1987 Camaro Iroc 350 Tuned Port Injection 42000Km 1987 Chevrolet Silverado 350 TBI 1987 Chevrolet Silverado 350 TBI(yes 2) Take me drunk, I'm too home... 
|
|
|
|
03-15-2014, 03:39 PM
|
#2 |
|
Registered User
Join Date: Jul 2013
Location: Hayden, ID
Posts: 12
|
Re: Can a tranny knock like an engine on start-up?
Cracked flex plate?
|
|
|
|
|
03-15-2014, 03:42 PM
|
#3 |
|
Robert Olson Transport
 
Join Date: Oct 2002
Location: recent transplant to NC USA
Posts: 20,310
|
Re: Can a tranny knock like an engine on start-up?
sounds like the flex plate if its not the motor
__________________
Bob 1951 International running on a squarebody chassis "If a man's worth is judged by the people he associates himself with, then i am the richest man in the world knowing some of the fine people of this board" http://67-72chevytrucks.com/vboard/a...t.php?f=25&a=9 (you can review the site rules here!) PM Me for your vehicle/parts hauling needs in the North East US or see my Facebook page Robert Olson Transport Live each day to the fullest.. you never know when fate is going to pull the rug out from under you... I hate cancer!! |
|
|
|
|
03-15-2014, 03:52 PM
|
#4 |
|
Right turn Clyde
Join Date: Nov 2002
Location: Cincinnati, Ohio
Posts: 2,911
|
Re: Can a tranny knock like an engine on start-up?
Take the inspection cover off the transmission and remove the torque convert bolts. That will help isolate the transmission from the engine noise. It will also allow a better view of the flexplate to check for stress fractures.
__________________
1974 C25 LWB: 454 4bbl Carb / TH400 / 3.73 1992 Camaro RS 305 TBI |
|
|
|
|
03-15-2014, 04:47 PM
|
#5 |
|
18 Till I Die
Join Date: Mar 2005
Location: Alberta, Canada
Posts: 1,522
|
Re: Can a tranny knock like an engine on start-up?
Only once a day first thing in the morning? If it was a flex plate wouldn't it do it on every start-up? I know I should roll under and take the cover off. Cold makes it worse.
__________________
2011 GMC Acadia 1969 GMC BBC LS7 2007 GMC Crew Duramax 1987 Camaro Iroc 350 Tuned Port Injection 42000Km 1987 Chevrolet Silverado 350 TBI 1987 Chevrolet Silverado 350 TBI(yes 2) Take me drunk, I'm too home...
|
|
|
|
|
03-15-2014, 05:33 PM
|
#6 |
|
Registered User
Join Date: Aug 2009
Location: Bowser
Posts: 13,731
|
Re: Can a tranny knock like an engine on start-up?
Could be detonation.
Easy to check, just pull the vac hose off the vac pot on the distributor and plug the hose (a golf tee works). Less messy too! |
|
|
|
|
03-15-2014, 09:18 PM
|
#7 |
|
Registered User
Join Date: Aug 2012
Location: Oklahoma City, OK
Posts: 2,611
|
Re: Can a tranny knock like an engine on start-up?
Had a noise like that start up a few weeks after installing a new crate motor. Turned out to be the power steering pump.
|
|
|
|
|
03-16-2014, 12:53 AM
|
#8 |
|
Registered User
Join Date: May 2012
Location: Ravenswood Wv
Posts: 86
|
Re: Can a tranny knock like an engine on start-up?
Unbolt torque and slide it back then fire it up the next mourning.
__________________
i do my burn outs in 4wd 
|
|
|
|
|
03-16-2014, 03:13 AM
|
#9 |
|
Registered User
Join Date: Jun 2013
Location: Oregon
Posts: 89
|
Re: Can a tranny knock like an engine on start-up?
I've experienced the same issue but with a different vehicle. Its a 95 bronco. the oil pressure started reading high then i noticed the knock at start up. started out loud then quieted down after 4-6 knocks. and yes it was only in the morning(after all the oil drained down back to the pan....) I changed spark plugs and oil. went with a 10w-40 instead of 10w-30. the knock stop instantly, but a few days later oil pressure started reading high again... still no knock. only thing i could think of is the oil pump could be taking a little to long to get the oil to top and down. reason i say that is switching to a heavier oil helped instantly, keep in the upper block longer.
__________________
79' c20 std cab 292 3speed granny - daily driver. 77' c30 std cab 454 th400 4.10 - fathers truck then mine. 95' ford bronco 302 4speed overdrive. 2002 mustang auto v6 - girlfriends daily driver. Debt just means that you had more fun than you're suppose to have |
|
|
|
|
03-16-2014, 09:37 AM
|
#10 |
|
Registered User
Join Date: Oct 2010
Location: Ocean Springs, MS
Posts: 1,746
|
Re: Can a tranny knock like an engine on start-up?
Piston slap. After they warm up and expand, it goes away till the next day.
__________________
Gary 1971 Chevrolet C/10 1951 GMC 100 1977 GMC C15 1955 Chevrolet 3100 |
|
|
|
|
| Bookmarks |
|
|
Hybrid Mode
