Hi everyone, I have noticed a knocking or thumping noise coming from the rear of my 246 GT. The noise only appears when the car is in a gear and is decelerating. No noise can be heard when in neutral. It also only starts to knock when the engine is warm. The faster I go, the higher the frequency of the noise. Any ideas?
I know this is going to sound really simple but start with the simple things first. That would be -- the tires. Then the rims and wheel nuts. Then the suspension bushings. Then the shocks. Then I would check the wheel bearings. Then work your way up to the transaxle. Don't always assume the worst first. It may be something simple.
Thanks, but as I said the noise only appears when the car is in a gear. Once I press the clutch it‘s gone. So wheels, tires, suspension are definitely not the problem.
1. Driveshaft issues, CV joints worn: Check rubber boots for damage. 2. Transfer gear issues: Suspend back wheels, set car in gear and listening for indications of worn transfer gears. Best regards Peter
Thanks for your help Peter! Do you think it‘s an issue I should immediately take care of or will it be fine if I wait until the season is over in October? Best regards, Ferdinand
Heres a video of the CV joint. When I move the left one there is a knocking noise. The right one does not make a noise. I think this could be it!
sounds like something has definately broken inside the CV joint, possibly the circlip on the half shaft, dont drive it until its fixed is my advice.
Indeed sounds like one of these parts...could well be a circlip failure or perhaps CV bearing issue. Kevin Image Unavailable, Please Login
It sounds like you have a very dry / worn bearing in one side. I would not be overly concerned by using the car for the rest of the season since these bearings are a very tough design. On the other hand it doesn't take long to remove the shafts and install new bearings. I would consider to change out all 4 bearings or at least the two outside bearings witch are the ones that takes the most beating. FYI, Porsche 911 from 198x used exactly the same type bearing joint and can be bought for less the Ferrari factor. Best, Peter
Thanks to everyone for your help!! I just made a quick „inspection drive“. I was able to narrow the noise down even more: The knocking sound is only heard when I decelerate with a gear in. It can not be heard when I accelerate. Could it be that the engine is just misfiring during deceleration?
Hi everyone, I found these replacement bearings from SKF: https://www.sparepartstore24.co.uk/19128-skf Can anyone tell me if they will definitely fit my Dino? Best wishes, Ferdinand
Your profile doesn't say but are you in the UK perhaps? Item Name Item Price Quantity Item Total --------- ---------- -------- ---------- 901-332-293-12-M60 $5.25 4 $21.00 CV Boot, 911/912 (1969-mid 75), 911 Turbo (1975-84) ---------------------------------------------------------------------- 930-332-034-00-M60 $92.25 4 $369.00 CV Joint, 911 Turbo (1977-84), Brand: GKN Loebro These are what I bought, but it appears they have dropped in price 20% ? https://www.pelicanparts.com/More_Info/93033203400.htm?pn=930-332-034-00-M60 PS - pack each one with at least 4oz of grease