We will now look at Locking hubs GM offered for 67-91 (mainly focused on the SPICER lockout) as well as (inside your truck cab) transfer case control lever ID. Many guys dont realize that crawling under your old muddy chevy to find out what T-case ya got isnt all that necessary. 98% of the time, you can tell what T-case you have just by looking at the shift knob, or lever. And for those possibly restoring their old chevy 4x4's, we'll look at what 4x4 control knob or even 4spd knob was used. What locking hub your old chevy would have come with.
I have assemble many pictures, either from the trucks I own, or from chevy or ford truck parts I have collected over the years....some of which are NOS. (new original stock)
1967-1972: During these years the locking hub was optional for GM 4x4s, but most trucks were purchased with them. During the 67-72 era GM only offered part time transfer cases that had (gear to gear) internal drive. The owner had the option of buying his chevy/gmc with either locking hubs.......or drive flanges. The drive flanges were (Full time) in the sense that the front axle was always engauged (front end parts spinning)...........while the T-case was in 2wd. This benefited the owner in that he didnt have to get out of his truck to lock in his hubs. However........it increased wear and tear on the front axle since everything was always spinning up front.............even in 2wd.
PRE 1970: 1969-back 3/4 ton GM 4x4s came with an all metal External bolt on locking hub with small turn knobs on them, these hubs were also used on 3/4 ton Fords of that era, and possibly some Dodges. Shown is a photo of the all metal locking hub...........a Full time drive flange used in mid/late 60's, (it was used with full time 4x4 in 70's also) The pair of metal knobs are 1/2 ton metal knobs, GM used an all metal 1/2 ton locking hub for pre 1968 trucks.
1969: GM began using the small internal Spicer locking hub on its 1/2 tons & K5 blazers. The locking knob was red plastic and was used 1 year only.
1970-71-72: In 1970 GM offered a new design of External bolt on locking hub for its 3/4 ton trucks which were all equipted with the HD44 front axle., It was a very heavy duty design, (over engineered some would say). The hub featured a large heavy chrome cap, with a thick steel housing for the hub internals. The hub gears were of hardend steel, with large coil spring and large allen head bolts. The actuating knob was of a plastic/nylon design which had a Spicer insert in the center of it.
Shown here is a set of very rare 70-72 Blue spicer hub knobs........GM only offered these for 70-72..........and the reason they were BLUE plastic..........is because it was color cordinated with the Chevrolet emblem which was also Blue. Collectors/truck restorer's today will pay a good price for a set of these in good condition..........since finding nos blue knobs anywhere is near impossible.
1973: GM switched its chevrolet emblem color to yellow..........so the Spicer hub knobs changed to a Yellow. The 70-72 Hub was the same as shown here........except for knob being yellow instead of blue.
By 1973 GM was offering ( Full Time 4wd)....which used no lockout hub. Spicer locking hubs were used only on (part time 4x4) trucks that came with the Np205 gear to gear T-case.
The Dana HD44 External Bolt on Spicer hub broken down for detail:
The coil spring is also massive in these.......compared to later style Warn hubs.......see comparision below.
Notice the size of the allen head bolts, they are extremely heavy duty.
The HD44 External bolt on Spicer Hub was used from 1970 to early 1977............(some sources will say 1976 was the last year they were used........but all GM or Chilton manuals say 1977.....I have seen a few early model production 77 K20's that came with the HD44...with either full time flanges or spicer hubs.
The HD44 Spicer hub did have a weakness.........and that was its plastic knob. While the hub design was simple.......and well designed..............Spicer hubs were not meant to be packed full of grease inside. They are meant to be LIGHTLY GREASED. If you put too much grease in Spicer hubs, come winter time.......the grease gets cold/hard...........and the hub knobs will turn super hard.......or will not lock in at all. So guys will grab a pair of pliers/ channel locks...........and try to turn them..............and this is what happens....................
Many spicer lockouts were chucked out.......for the simple fact that too much grease was packed into them......causing failure...making 4x4 owners think they were junk.
Here is a WARN external bolt on hub for the HD44, the design is simple, easy to use, but unlike the Spicer, the Warn uses 4 small coil springs for engaugement.......these springs are small compared to the large coil spring of the spicer. The Hub gears are also much smaller than the Spicer.
Those who run external bolt on spicer hubs might wonder if they can still get parts for them. As of 2000 the only parts I could buy NEW from the GM dealer were 73-77 yellow locking knobs, and housing gaskets. Everything else had been discontinued since the mid 80's. Now....9yrs later....everything is discontinued. There are still used & NOS parts out there floating around. EBAY......is a good place to check for, and buy parts. I've collected up some NOS parts over the years for these hubs. Most peaple who would buy NOS parts like this, are either to restore a 4x4 or to collect. These parts are much more valuable as a collectable
Here is a brand new Chrome outter housing.
These are FORD NOS Spicer hub knobs for 1977-back F-250 Hi-boys........these knobs are still available on ebay, for around 40/60.00. These will work on chevy HD44 hubs (ford used the large spicer hub in the 70's also)
These are NOS 73-77 Yellow knobs, these can still be found on ebay also, but tend to be pricey, I've seen them sell for around 100.00 a set
This red GM replacment knob doesnt say (spicer or ford ) on its turn knob. GM apparently offered red knobs as a replacment part. The red knobs were not offered on GM trucks made from 70-77, only blue or yellow were used.
For those looking for maximum strength for a spicer HD44 hub...........these machined billet aluminum knobs will solve any breakage problems associated with the plastic knobs. I run these on my 67 gmc k2500.
Around 1968/69 GM began to offer a spicer 1/2 ton locking hub, this was used until around 1981/82, the design did not change other than the color of the locking knob, red plastic for 68/69, blue plastic knobs being used for 70-72 models....yellow plastic for 73-82. The 1/2 ton spicer has a few more internal parts than the larger 3/4 ton hub.
1/2 ton Spicer hub broken down.
The engaugement gears.........I've seen a 2nd style of the smaller gear used in these hubs....apparently GM did a change over at some point switching to a 2nd design.
Shown for comparison of size.......the HD44 spicer is a massive lockout compared to the 1/2 ton spicer.
Full Time 1973-up 1/2 ton & 77 1/2-up 3/4 ton Hub. This design was used on GM....Ford..........Not used by Dodge in 70's.....as Dodge used a Hubless front axle design on it's 1/2 tons. Quadratrak fullsize Jeeps used this also.
1982: AUTO LOCKING HUBS, this was introduced alongside the 700R4 tranny.....both were seen on 1982-up GM 4x4s. The auto locking lub was a revolutionary design.......enabling the driver to shift into 4wd without locking in the hubs........and at the same time, while in 2wd.........nothing in the front axle was engauged/turning. Auto locking hubs were offered on ALL models....K5... k10 K20....and K30.
Auto Locking hubs enguaged upon the T-case being shifted into 4wd.........front driveshaft begins to turn......and this enguages mechanical gears/couplers inside the hub. Disengaugment consisted of putting T-case lever back in 2wd......and backing the vehicle up 15/20ft. NOTE:........if you dont back the vehicle up.......the hubs will stay engauged........and with windows down........you will be able to HEAR a CLICKING sound coming from the front axle...........that means the hubs are still locked in.
PROBLEMS with Auto Hubs: Since these operated on rotation of the front driveshaft........it was posssible for a person stuck in the mud to hit reverse...........and in doing so...........this disengauges the hubs........but locks them back in at the same time....because the T-case is still engauged. Also the hubs were also prone to STICK....in the lock position......even after backing up to disengauge them. Under normal use.........they worked fine..............but for a snow plow truck for example........they wouldnt last long. Many owners who opted for auto hubs later swapped them out for manual hubs for better reliability.
1982-87: Spicer hubs were no longer used, In these years GM was offering Auto locking hubs......and Warn manual hubs on its trucks.
87-91: K5 blazers....suburbans.....and old body style 1 ton K30's........these still had solid front axles.....and either came with Auto hubs or manual locking hubs.
.........................GM TRANSFER CASE LEVERS AND CONTROL KNOBS......................
np205: GM used 2 styles of NP205 levers............1st design was 69-72......2nd design was 73-91. Only difference is in length and lever angle........69-72's have a longer shift rod which arches back toward the driver. 73-up 205 levers are shorter. GM offered different trim packages in its trucks, and as such...........a Chrome plated lever was used in (loaded) models while a black painted version was used in stripped down models. ALL GM 205 levers are ROUND STEEL ROD construction.........not to be confused with a Np203 lever....which is flat sqaure/rectangular.
Shown here is a mid 80's NP205 lever.............along side a mid 70's Np203 lever...........notice the differences.
SHift knobs used on GM NP205s........1969-----1991......this will tell you what your truck should have come with....note the 82-84 knob.....the shift pattern would have been engraved on it.....I had to used the 82-84 Np208 knob since I didnt have a 82-84 engraved style 205.
NP203: GM used 2 types of shift levers from 1973-1979.....1st design was used 73-78........2nd design was for 1 year only and that was 1979. Early NP203 levers......73..74...75 are Engraved HURST on the side of them. They were made by the Famous Hurst shifter company for GM. (( see Np205 lever photo for pic of 203 lever). ALL 203 levers are Chrome plated.
203 shift knobs: Again 2 designs 73-78 with engraved 4x4 frame..........79 had range pattern engraved on the knob (this did away with the earlier 73-78 style metal range plate at the base of the lever. (79 Np205s switched over to this as well). The 1979 style knob WILL NOT fit 73-78 levers.........the threading....and hole diameter is smaller.
203 lever boots: 2 designs used....73-78.....and 1 yr only 1979. The 73-78 pattern used a thin rubber boot with metal base plate....with range plate. The 1979 version used a steel inserted thick rubber molded boot with a large metal base plate ring.
NOTE:......Np205 boots for 73-78 are the same as Np203s.......except the lever hole in the boot is ROUND....not sqaure......but they will interchange with each other. In 1979 the NP205 boot switched over to 203 style as well.........and this was used until 1991.
NP208 Levers: GM used only 1 style of lever......they were all chrome plated.........I am showing pics of the lever housing & upper linkage arm as well.
NP208 knobs: GM used 3 styles.......the rare 1981 version will not fit 82-up 208 levers.......threading is different. Also the 81 knob design is a carry over from the previous (mid 70s) 203/205 knobs. The 1982-1984 version looks like a pool ball. The 85-91 version is a leather textured type........which was used up till 1994 on GM 4x4s.
SM465 SHift knobs used from 1968-1991.
