BigVan
Registered User
Hello all. I’m a long time lurker and learner but don’t post much on any platform.
Short of it, I have a loud high pitched whistle (not a bearing squeal) like noise and a low rumble from the rear differential (90% sure), but only at speeds over 65 and only on a very light throttle throttle. Nothing at lower speeds. Nothing accelerating and nothing while slowing down. No change with curves either side. Nothing feels hot after a 20 mile drive. No change with road surfaces. It’s a van so I know it’s a giant amplifier inside but it’s driving my dog and me insane. If I’m looking forward it’s loud and from the back/center, turn my head to listen and sort of it goes away. Details below.
91 E350, NA 7.3IDI
315 70R17
D60 rear and D60 Kingpin Front
3.54 gearing
Sometime last year the pinion nut worked itself loose in the middle of Canada heading down to New Mexico for work. The yoke actually came off at a stoplight and after removing the rear drive shaft and limping it to the nearest auto store with a parking lot patch job I was back on the road. I didn’t have an option to wait due to COVID regs. It made it here… then the pinion bearing cage came apart and locked up destroying everything in the process at about 50 miles an hour.
So I tore into it. Flushed the axle, replaced all bearings and races, installed a Yukon ring and pinion replaced U-joints with spicer lifetimes and took it for a drive. It started making noise again which I figured out was a pinion race that had moved about .003 due to not seating all the way. While changing the oil after around 500 miles, I noticed a slight wear (shiny) pattern on the ring gear so I tore into it again and replaced the pinion bearings and races.
My settings are below. The specs I used came from the Yukon install guide.
Runout max was .002
Backlash .007
Pinion rotational preload 22 inch pounds
Pinion nut 250 ft pounds (with red lock tite)
Drive and coast pattern ideal and checked in multiple spots.
Carrier preload was enough that I could barely start it and then had to seat it with deadblow. (Don’t have a case spreader)
All bolts torqued to spec.
Filled with a bottle of lsd additive and 85W gear oil.
Of note, maybe a separate issue but I borrowed a chassis ear a while back before all this mess and the Transfer case wasn’t loud but you could definitely hear the chain with that I interpreted as a bit of slack. Changed the ATF out of it and it was nearly black.
Took it to a trans shop and shelled out some $$$ for them to tell me the transmission has no issues.
The only thing I can think of is the carrier had a slightly loose fit (I dimpled it with a punch to press on) and maybe spinning under the higher rotational force under the bearing mounting surface? I have no idea. This thing has to make a 3600 mile drive in a few short weeks and I need to know it’s not going to lock up again.
Ideas???
Short of it, I have a loud high pitched whistle (not a bearing squeal) like noise and a low rumble from the rear differential (90% sure), but only at speeds over 65 and only on a very light throttle throttle. Nothing at lower speeds. Nothing accelerating and nothing while slowing down. No change with curves either side. Nothing feels hot after a 20 mile drive. No change with road surfaces. It’s a van so I know it’s a giant amplifier inside but it’s driving my dog and me insane. If I’m looking forward it’s loud and from the back/center, turn my head to listen and sort of it goes away. Details below.
91 E350, NA 7.3IDI
315 70R17
D60 rear and D60 Kingpin Front
3.54 gearing
Sometime last year the pinion nut worked itself loose in the middle of Canada heading down to New Mexico for work. The yoke actually came off at a stoplight and after removing the rear drive shaft and limping it to the nearest auto store with a parking lot patch job I was back on the road. I didn’t have an option to wait due to COVID regs. It made it here… then the pinion bearing cage came apart and locked up destroying everything in the process at about 50 miles an hour.
So I tore into it. Flushed the axle, replaced all bearings and races, installed a Yukon ring and pinion replaced U-joints with spicer lifetimes and took it for a drive. It started making noise again which I figured out was a pinion race that had moved about .003 due to not seating all the way. While changing the oil after around 500 miles, I noticed a slight wear (shiny) pattern on the ring gear so I tore into it again and replaced the pinion bearings and races.
My settings are below. The specs I used came from the Yukon install guide.
Runout max was .002
Backlash .007
Pinion rotational preload 22 inch pounds
Pinion nut 250 ft pounds (with red lock tite)
Drive and coast pattern ideal and checked in multiple spots.
Carrier preload was enough that I could barely start it and then had to seat it with deadblow. (Don’t have a case spreader)
All bolts torqued to spec.
Filled with a bottle of lsd additive and 85W gear oil.
Of note, maybe a separate issue but I borrowed a chassis ear a while back before all this mess and the Transfer case wasn’t loud but you could definitely hear the chain with that I interpreted as a bit of slack. Changed the ATF out of it and it was nearly black.
Took it to a trans shop and shelled out some $$$ for them to tell me the transmission has no issues.
The only thing I can think of is the carrier had a slightly loose fit (I dimpled it with a punch to press on) and maybe spinning under the higher rotational force under the bearing mounting surface? I have no idea. This thing has to make a 3600 mile drive in a few short weeks and I need to know it’s not going to lock up again.
Ideas???