Introduction and question

78chief · October 06, 2023, 10:06 AM

Hi new here my name is mike and i just bought my first rv and my first classic winne. 1978 winnebago chieftan. Working on getting it into shape. This site is great and i have already found many answers here. Here is my question does anybody know part numbers or diemensions for the front and rear lug studs i have to replace some and was hoping to order them before i tear it appart. I have the dana 70 dual wheel rear axle. Thanks mike

78chief · October 06, 2023, 10:08 AM

Also thanks dave your brake info at daves place has been a life saver.

Oz · October 08, 2023, 06:43 AM

Hello and welcome! There's a wealth of info support for you here to help you along the way.

BigAlsVehicleEmporium · October 08, 2023, 09:30 AM

Hi 78 Dave,

Do you know what chassis it's on? My parts book and recently acquired knowledge only applies to the Dodge chassis up through '77.

DaveVA78Chieftain · October 08, 2023, 10:17 AM

1974 - 1979 M300/M400 chassis
Dodge P/N 3637878

Dorman 610-215.1

78chief · October 09, 2023, 08:50 AM

Sorry for the slow reply i did not get an email or anything so i did not notice people had replied till i checked again. Thanks dave for the rear lug stud part number still working on the front stud part number you wouldn't happen to know that also would you? Thanks mike

78chief · October 09, 2023, 09:33 AM

Quote from: BigAlsVehicleEmporium on October 08, 2023, 09:30 AMHi 78 Dave,

Do you know what chassis it's on? My parts book and recently acquired knowledge only applies to the Dodge chassis up through '77.

1974 - 1979 M300/M400 chassis

RockwoodMike · October 09, 2023, 10:15 AM

https://www.rockauto.com/en/parts/dorman,610215,lug+stud,7680

Just did a search on RockAuto..They are on closeout

Looks like the same part number that Dave mentioned earlier..

78chief · October 09, 2023, 10:23 AM

Quote from: RockwoodMike on October 09, 2023, 10:15 AMhttps://www.rockauto.com/en/parts/dorman,610215,lug+stud,7680

Just did a search on RockAuto..They are on closeout

Looks like the same part number that Dave mentioned earlier..

I have em in my cart already at rock auto lol just trying to figure out part number for the fronts so i can order those at the same time. Thanks

RockwoodMike · October 09, 2023, 11:34 AM

https://www.rockauto.com/en/tools/wheel,hardware,lug+stud,7680

You may need to remove one of your bad studs and measure it with a micrometer to check against this large selection at RockAuto

BigAlsVehicleEmporium · October 09, 2023, 01:58 PM

Quote from: 78chief on October 09, 2023, 10:23 AMI have em in my cart already at rock auto lol just trying to figure out part number for the fronts so i can order those at the same time. Thanks

Attached is the part number listings for the front nuts and studs. The columns for chassis/axle and the quantity should narrow it down to what you have!

78chief · October 09, 2023, 09:24 PM

Quote from: BigAlsVehicleEmporium on October 09, 2023, 01:58 PM
Quote from: 78chief on October 09, 2023, 10:23 AMI have em in my cart already at rock auto lol just trying to figure out part number for the fronts so i can order those at the same time. Thanks

Attached is the part number listings for the front nuts and studs. The columns for chassis/axle and the quantity should narrow it down to what you have!

Thanks for the info that crosses to a dorman 610199 for the front stud but the look and measurements are off from the one i removed today. From what i can find dorman 610072 looks like mine and the measurements line up with mine too im going to order that one and i will report back once i replace them with current part numbers in case it come in handy for anyone else in the future thanks for the replys everyone.

DaveVA78Chieftain · October 09, 2023, 11:48 PM

The 78 Chieftain (26RB) was on a M400 chassis. Which for the front disc is Dodge P/N 3640138. Because of the larger M400 axle, the rotor hubs are a lot different between M300 (single caliper) and M400 (dual caliper). Front studs appear to be a difficult item to locate. This is a case where it could be listed under a either a M400 or RM350 chassis designation. Try NAPA using 1974 Dodge M350.

78chief · October 12, 2023, 11:15 PM

Stupid question but does anybody know on a dana 70 is the spindle nut torqued to a certain spec or just snugged while spinning the drum like a trailer spindle nut. Im a mechanic by trade but this rig is way before my time.

RockwoodMike · October 13, 2023, 08:57 AM

I just rebuilt my Dana 70 on my 73 Indian..The Pinion nut on it was spec of 250-275 Foot pounds..

But if your spacers on the pinion are worn down from being loose on the pinion nut, it will cause the preload on the pinion bearings to be too tight and will burn up your bearings..

The spacer shims on the pinion, if the pinion nut has been loose, will crush down because of the looseness..The pinion will slam back and forth..Like a hammer on the shims..
And then when you retighten the spindle nut, it will bind the bearings..

RockwoodMike · October 13, 2023, 10:12 AM

When the differential was new, the pinion bearings preload was established using shims..and that sets the distance between the bearings..Too small on the pinion shim stack and the bearings will be too tight for the preload..
Too tall on the shim stack and the bearings will be too loose..
.001 of a shim stack makes big difference in bearing preload..

So as time wears everything down, you start to get slop in the bearings..The shims get hammered due to the slop creating even more slop..

You come along and tighten the pinion nut to 250LBs and because the shims are crushed, it causes the preload to be way too tight..

When I pulled my diff out, it actually had fragments of shims floating around..just from the slop hammering on them..

The backlash between the pinion gear and the ring gear was way out of spec..suppose to be 5-8 thousand new and mine was 11 thousand..

I completely rebuild mine with new bearings, ring and pinion..It is not an easy job..

Elandan2 · October 13, 2023, 04:23 PM

According to the service manual, the wheel bearings on a Dana 70 are adjusted as you said, "rotating the wheel and tire assembly until a slight drag is felt and then back off the adjusting nut 1/6 turn so that the wheel will rotate freely without excessive end play".

RockwoodMike · October 13, 2023, 04:40 PM

Well that was stupid of me..I thought he was talking the pinion nut..As Rosanna Anna Danna said.."Never mind"

78chief · October 13, 2023, 06:30 PM

Yep i am talking about the spindle or hub nut. Thanks for the replys.

Eyez Open · October 13, 2023, 07:58 PM

Quote from: Elandan2 on October 13, 2023, 04:23 PMAccording to the service manual, the wheel bearings on a Dana 70 are adjusted as you said, "rotating the wheel and tire assembly until a slight drag is felt and then back off the adjusting nut 1/6 turn so that the wheel will rotate freely without excessive end play".

Most heavy duty axles/wheel bearing tourqe down are done just as above. There is a sequence we used in the shop however.

Tighten down and rotate the hub, tighten down to a full hub lock.

Loosen the hub and rotate until the hub locks again. 3 times is not unusual final turn as descibed above.

Your pressing the bearing/race assembly to a close. So far never a burnt bearing....lol so far. Pinching in a bearing into the race is highly improbable this way.