Ticking noise in granny low - The 1947 - Present Chevrolet & GMC Truck Message Board Network

rScotty · 02-13-2014, 06:27 PM

Our truck is a '70 chevy 4x4 with a 4 speed manual tranny and like so many Chevy pickups it has the typical manual 4 speed non-syncro, very low, and seldom used 1st gear. It's what's called a "granny gear". We've had it for decades....

I was showing off the truck to a friend and noticed that in that gear I can hear a clicking or ticking noise about twice a second as we go forward slowly on pavement in 2wd mode. It's only in that gear, but it's very definite and very regular. Maybe as some gear revolves? There's a lot of general gearbox noise anyway when we're in a gear that low but I can hear this if all is quiet. It's not a loud heavy sound, but you can't miss it. Definite. About as loud as a rock in a tire tread, but this only happens going forward - noise isn't there in reverse. There's either none or very little accompanying vibration when it clicks - not enough to feel through the wheel, seat, or body - although maybe I can just feel it with a finger on the shifter. Basically it's just a soft click-click sound about twice a second as we go forward in low.

Unfortunately we don't know how long it has been making this sound in granny low. That gear is rarely used anyway - it might be years between uses for a gear that low. And I do tend to loan the truck out. Everything else seems fine/unchanged. Might have been that way for years...or maybe no
What is it? Anyone know? Theories?
thanks, rScotty

TonyJohnson · 02-13-2014, 08:33 PM

I've got that sound in 4hi... Hopefully an answer, soon. You might ask in the 4x4 section of the board, as well.

beetle1960 · 02-13-2014, 10:00 PM

Possibly a Chipped tooth on the gear.

Carl Spangler · 02-14-2014, 01:12 AM

I'd try an oil change. Maybe use a slightly thicker oil than stock. FWIW, I used 80W90 in my M465 and it runs pretty quiet.

good luck
JohnG

TonyJohnson · 02-14-2014, 01:58 AM

Mine varies depending on clutch/engine speed it feels like something is out of alignment...
I'm gonna crawl under there and see if I can see any wear or obvious problem. otherwise, I suspect alignment. I've got a 4" lift and the front DS has a pretty steep angle.

69GMCLonghorn · 02-17-2014, 05:18 PM

In granny gear, you are generating a lot more torque than usual. The sound may not seem to fit, but it could be a U joint..

02-13-2014, 06:27 PM	#1
rScotty Registered User Join Date: Oct 2011 Location: Rural USA Posts: 3	Ticking noise in granny low Our truck is a '70 chevy 4x4 with a 4 speed manual tranny and like so many Chevy pickups it has the typical manual 4 speed non-syncro, very low, and seldom used 1st gear. It's what's called a "granny gear". We've had it for decades.... I was showing off the truck to a friend and noticed that in that gear I can hear a clicking or ticking noise about twice a second as we go forward slowly on pavement in 2wd mode. It's only in that gear, but it's very definite and very regular. Maybe as some gear revolves? There's a lot of general gearbox noise anyway when we're in a gear that low but I can hear this if all is quiet. It's not a loud heavy sound, but you can't miss it. Definite. About as loud as a rock in a tire tread, but this only happens going forward - noise isn't there in reverse. There's either none or very little accompanying vibration when it clicks - not enough to feel through the wheel, seat, or body - although maybe I can just feel it with a finger on the shifter. Basically it's just a soft click-click sound about twice a second as we go forward in low. Unfortunately we don't know how long it has been making this sound in granny low. That gear is rarely used anyway - it might be years between uses for a gear that low. And I do tend to loan the truck out. Everything else seems fine/unchanged. Might have been that way for years...or maybe no What is it? Anyone know? Theories? thanks, rScotty

02-13-2014, 08:33 PM	#2
TonyJohnson Registered User Join Date: Mar 2003 Location: Cheboygan, MI Posts: 998	Re: Ticking noise in granny low I've got that sound in 4hi... Hopefully an answer, soon. You might ask in the 4x4 section of the board, as well. __________________ Tony Johnson -- '71 Blazer w/L-31 Vortec 350, SM465, NP205, performer intake, edelbrock 1406, HEI, 4" lift, Boyd EFI tank, Vintage A/C My Blazer --

02-13-2014, 10:00 PM	#3
beetle1960 Registered User Join Date: Aug 2013 Location: Hiram Ohio Posts: 619	Re: Ticking noise in granny low Possibly a Chipped tooth on the gear. __________________ 1953 Chevy 3100 1964 Chevy Impala 1966 Chevy El Camino 1970 Chevy C10 Fleet Long 1972 Chevy C10 Step long 1985 Chevy K10 Fleet Short

02-14-2014, 01:12 AM	#4
Carl Spangler Registered User Join Date: Oct 2013 Location: Central Coast Ca. Posts: 417	Re: Ticking noise in granny low I'd try an oil change. Maybe use a slightly thicker oil than stock. FWIW, I used 80W90 in my M465 and it runs pretty quiet. good luck JohnG

02-14-2014, 01:58 AM	#5
TonyJohnson Registered User Join Date: Mar 2003 Location: Cheboygan, MI Posts: 998	Re: Ticking noise in granny low Mine varies depending on clutch/engine speed it feels like something is out of alignment... I'm gonna crawl under there and see if I can see any wear or obvious problem. otherwise, I suspect alignment. I've got a 4" lift and the front DS has a pretty steep angle. __________________ Tony Johnson -- '71 Blazer w/L-31 Vortec 350, SM465, NP205, performer intake, edelbrock 1406, HEI, 4" lift, Boyd EFI tank, Vintage A/C My Blazer --

02-17-2014, 05:18 PM	#6
69GMCLonghorn Registered User Join Date: Dec 2006 Location: Porter Ranch, CA Posts: 978	Re: Ticking noise in granny low In granny gear, you are generating a lot more torque than usual. The sound may not seem to fit, but it could be a U joint..



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