Hi Jim, Google "spider gears" view associated pictures and you will see why one wheel turns and the other doesn't. It is that cluster of four gears that allows for a difference in speed between the rear wheels as you turn corners or loose traction and spin one of the rear tires.
With respect to your knock if it is irregular and happens over bumps etc., it could be from anything that moves with or comes in contact with the suspension. If it is regular and occurs at the same frequency as wheel rotation it should be in the driveline between the differential and the wheel rim. If it is regular and occurs about 4 times each wheel revolution then it is in the driveline from the differential forward to the transmission. ....Spitman.... -----Original Message----- From: Spitfires [mailto:[email protected]] On Behalf Of Jim Cullen Sent: Monday, July 14, 2014 10:30 AM To: [email protected] Subject: [Spits] Rear End Noise.... dumb question Hi listers..... I wonder if I could get some insight/advice on a knocking noise that seems to be coming from the RH side of my rear end. I notice it more @ once I get up to about 50 km/hr, especially over bumps (to the point I thought it was the shock absorber and replaced that to see if it disappears as it seemed to sound like the shock absorber was b bottoming outb b unfortunately, no joy there), and when making left turns. After doing some research (see link b http://www.britishcarforum.com/bcf/archive/index.php/t-28039.html) I thought it might be the uv joint for the RH driveshaft (note that these were replaced relatively recently, but from reading the experiences of others the relative b newnessb of the driveshaft may not preclude the uv joints of the driveshaft from being the culprit). I have the car now jacked up and have done an inspection of the uv joints. I donbt see any evidence of play in the uv joint and the circlips on the joint appear tight. Is there a better way to diagnosis the uv joints a possible issue? I thought I should check the propshaft uv joint too, but this seems okay too. Here is my dumb question, with the car jacked up and in neutral when I hand turn the prop shaft I note the LH side drive turns in unison with the propshaft, but the RH side doesnbt (it lags or doesnbt turn). I know I should know if this is an issue, but despite having this car for close to 20 years and doing most of the work on it myself (as well as being an eager, but novice mechanic) I essentially know very little about the differential (other than what I learned from the Haynes manual and from when I replaced the driveshafts a year and a half ago). So, my dumb question is two part..... is what I b describedb normal? if no.... could it be the source of my rear end noise (differential needs to be replaced)? I hesitate to name the differential as the culprit, because most of my research seems to suggest differentialbs donbt knock like mine is (they b whine), but given my novice intelligence about differentialbs Ibm not really sure. Anyhow, I would appreciate some insight Thanks for the help, Jim Cullen 1974 Spitfire _______________________________________________ [email protected] Donate: http://www.team.net/donate.html Suggested annual donation $11.47 Archive: http://www.team.net/archive Forums: http://www.team.net/forums Unsubscribe/Manage: http://autox.team.net/mailman/options/spitfires/[email protected] --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com _______________________________________________ [email protected] Donate: http://www.team.net/donate.html Suggested annual donation $11.47 Archive: http://www.team.net/archive Forums: http://www.team.net/forums Unsubscribe/Manage: http://autox.team.net/mailman/options/spitfires/[email protected]
