Rattle can noise when accelerating from stop

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Radiohead

That guy on the Columbia
Joined
Mar 17, 2022
Posts
2,486
Reaction score
8,110
Location
Low Earth Orbit where it's safer
First Name
Eric
Truck Year
MCMLXXIX
Truck Model
C-20 Silverado Camper Special
Engine Size
454 crazy cubes, or 7.4 luscious litres
If its automatic trans, are all the torque converter bolts tight?

I don't see how pre-detonation goes away after a certain speed, unless it has esc and its gone gunnybag.
 

SmallsTX

Junior Member
Joined
Nov 28, 2018
Posts
26
Reaction score
14
Location
Central TX
First Name
Patrick
Truck Year
1980
Truck Model
C35
Engine Size
454
Put it in drive,left foot brake hard givevit some gas that will eliminate all the drive train if it rattles while powerbraked.
heres what is does with foot on brake
xc_hide_links_from_guests_guests_error_hide_media
 

Rusty Nail

Full Access Member
Joined
Jan 29, 2015
Posts
10,041
Reaction score
10,134
Location
the other side of the internet
First Name
Rusty
Truck Year
1977
Truck Model
C20
Engine Size
350sbc
That's tough after the 2nd video - a very curious sound. Now i'm gonna say "broken valvespring".

Uhh.. #3 or #5 exhaust valve. Prolly 5

xc_hide_links_from_guests_guests_error_hide_media

How you like them apples?
 
Last edited:

Rusty Nail

Full Access Member
Joined
Jan 29, 2015
Posts
10,041
Reaction score
10,134
Location
the other side of the internet
First Name
Rusty
Truck Year
1977
Truck Model
C20
Engine Size
350sbc
I listened again to the second video. Definitely not a valvespring...the exhaust note remains consistent. Soooo it's not related to valvetrain it's something different - it's not misfiring.
Do it again but get on it harder. Force the noise if you can.

xc_hide_links_from_guests_guests_error_hide_media
 

TotalyHucked

Full Access Member
Joined
Feb 24, 2020
Posts
3,671
Reaction score
11,861
Location
Auburn, Georgia
First Name
Zach
Truck Year
1985
Truck Model
Sierra 1500
Engine Size
5.3
Huh. That's a very odd noise. What kind of mufflers do you have? Maybe a baffle has broken loose? I'd also take off the inspection cover and make sure the flexplate/converter bolts are tight.
 

squaredeal91

Full Access Member
Joined
Mar 10, 2023
Posts
2,538
Reaction score
4,584
Location
Cave junction Oregon
First Name
Greg bush
Truck Year
1991 SB
Truck Model
K30
Engine Size
5.9 Cummins 12 valve
If its automatic trans, are all the torque converter bolts tight?

I don't see how pre-detonation goes away after a certain speed, unless it has esc and its gone gunnybag.
I agree. After 2nd video. I'm thinking torque converter bolts or cracked flexplate.
 

TotalyHucked

Full Access Member
Joined
Feb 24, 2020
Posts
3,671
Reaction score
11,861
Location
Auburn, Georgia
First Name
Zach
Truck Year
1985
Truck Model
Sierra 1500
Engine Size
5.3
Oh yeah, @squaredeal91 very well could be on to something with the cracked flexplate. Had one in my K5 years ago do that exact thing and the flexplate had a crack almost all the way around, just outside where it bolted to the crankshaft.
 

SmallsTX

Junior Member
Joined
Nov 28, 2018
Posts
26
Reaction score
14
Location
Central TX
First Name
Patrick
Truck Year
1980
Truck Model
C35
Engine Size
454
alright, well thanks everyone for all the helpful input, i found out it is in fact the flex plate, i have a date to take it back to my mechanic since i dont have time to do anything myself at the moment.
 

Latest posts

Forum statistics

Threads
44,168
Posts
950,783
Members
36,283
Latest member
Cantrell299
Top