El Camino Central Forum banner

1 - 15 of 15 Posts

39 Posts
Discussion Starter #1
I’m planning on doing a mild upgrade of the 200-4R for my ‘64 El Camino, 350 sbc, nothing special yet. I now have it completely disassembled. The overrun clutch assembly housing, #510 of the ATSG manual, is worn and has a rough surface as pictured. Does it need to be replaced or would it be ok to smooth the edges with Emory cloth and sand paper?

Premium Member
4,389 Posts
I am not sure if the answer is in this thread, yet it will bring up some more thoughts.

31 Posts
In my opinion it should be replaced. The wear being concentrated on one side is my concern. I'm not an expert but have built several of these. Can ship one to you if you're interested.

Premium Member
935 Posts
I’m planning on doing a mild upgrade of the 200-4R for my ‘64 El Camino, 350 sbc, nothing special yet. I now have it completely disassembled. The overrun clutch assembly housing, #510 of the ATSG manual, is worn and has a rough surface as pictured. Does it need to be replaced or would it be ok to smooth the edges with Emory cloth and sand paper? View attachment 127666 View attachment 127667
I'm no transmission expert but that kind of ground up part will warrant replacement every time! Also, I just looked at it again and there looks like a crack on the right side of the pic. Yep, replace.


39 Posts
Discussion Starter #6
Thanks for the input. I haven’t been able to find a hardened one, same with the turbine shaft.
White lightening, how much do you want for the one you have?

39 Posts
Discussion Starter #9
The planetary gears fell out after removing the turbine shaft from the overrun drum. How do you replace them? There’s 19 rod bearings and it seems really difficult to put it back where it belongs.


39 Posts
Discussion Starter #10
How much wear on the pump is tolerable? As you can see there’s a slight groove around 70% of the stator shaft where the pump means the pump rotor. Does the pump need to be replaced?

79 Posts
I am not a trans expert but my 2 cents when it comes to rebuilding your own trans is when in doubt replace it. If you are asking if it should be replaced in most cases you are correct it should be. Also for the price of a full rebuild kit for this trans I would replace everything but the case. good luck on the rebuild!!!

39 Posts
Discussion Starter #12 (Edited)
If anyone is thinking about doing a 200-4R rebuild it's not too difficult. I was fortunate to find good books and the DVD which isn't sold anymore. I got a lot of help from Grumpys Performance Garage
Below are some of my notes. I may upload a word document or pdf in the future if it's possible.

TH200-4R GM Transmission Rebuild Assembly

Salvage yard 200-4R (lkq pick-a-part, $200)…ideally buy two after 1985. Get speedometer cable, throttle valve cable, dipstick etc.

54008B deluxe kit (comes with 12 bushings, carid.com, $137)
Bearings (54201B, Transmaxx on Amazon, $8)
Washer kit (C7339B, TruTrans on Amazon, $7)
Pump washer (65420D, TruTrans $7)
Selective washers (54268K/L/M, cobratransmission.com, $3)
Solid Teflon rings (qty 5, 54177BST, cobra, $10)
Billet servo (betperformance, ebay, $75)
Hardened pump stator (ebay, $20)
Hardened rings and stiffer spring (T74165HP, Transgo, ebay, $15)
.500 sonnax Throttle Valve (7791704K, TruTrans $7)
.283 reverse boost (A74507RBK, TruTrans, $7)
Lock up solenoid (ebay, $20)
Oil pan drain (Dorman 65128, $6)
700-4R filter (74011F, Cobra, $10)
Assemblee Goo (Ebay, $7)
Front seal retainer (w/ seals EASU4L60 $12 or Cobra $1.50)
Spring A74741N-3, Anti-Stick Throttle Valve Spring, cobra
Thicker direct steel 511769, 0.100” (Transmaxx, $6)
651, extra wave spring, 86282222, (monster, $6)
DIY shift kit

Total parts ~$360

Other parts:
Trans Cooler
May need to find or make oil pan spacer with sheet metal to be able to use 700-R4 filter

200-4R Modifications According to ATSG part numbers

Pump Modifications: ATSG pg. 20, 93
4, hardened pump stator shaft
9, drill and chamfer pump washer?
203, 217 Drill pump drain back holes 0.25”, CK pg. 33
Add red loctite on pump seal and use seal retainer
212, hardened pump rings
209, stiffer spring or dual spring
214, ten vane rotor (not needed)
223, 222, 221, 220, .500 throttle valve and .283 or .296 reverse boost,
219, stiffer pressure regulator spring, (Sonnax 77917-08, 1.93x0.52”x0.040”)
225, make sure clip reinstalls with rounded edge towards valve
232, install washer between pin and spring, protects spring
236, drill cup plug to 0.045", pg 29

Internal Modifications: ATSG pgs. 89-91
19/16 replace with billet, 21 discard o-ring, consider pin extender, CK pg. 75
507-508, drill 4 holes through steels 0.0625”…compare to 8 holes at 0.125", CK pg. 49
534, machine down to 1.630" (remove 0.080"), adds extra friction plate between two steels, pg. 49
539, Dual feeding direct clutch, remove middle seal of center support (537), plug oil feed hole (538) w/ spare check ball from salvaged governor, CK pg. 72
601, wide band Alto Red Eagle, (P43961, optional, high performance, requires machining drum)
618, billet forward clutch shaft (billet $460, hardened $200, high performance)
604, drill 0.060" bleed hole at 45 degree angle, CK pg. 60
640, Hardened sun gear shell was OEM after 1985
633, enlarge existing holes to 0.150" and add holes, CK pg. 81
636, lube hole 0.125", CK pg. 80
646, drill 0.060"bleed hole in corner, CK pg. 85
651, add extra wave spring, CK pg. 85

Crosshatch steel plates with emory cloth on side that touch friction plates.
Crosshatch direct drum. Use a straight edge to make sure it isn’t warped.
Governor, tap the secondary weight for an aluminum 8-32 screw to hold spring

Valve body plate (#56): ATSG pg. 22, CK pg. 111
#5, drill to 0.11”, if it binds drill additional 0.005” (high performance only), CK pg. 72
#8, drill to 3/32” (0.09375)….compare to transgo 0.072, CK 0.140”
#14, 3rd clutch drill to 5/64” (0.078)….compare to CK 0.140”
#18, Orifice drill to 3/32” (0.09375) ….compare to transgo 0.072, CK 0.125”
#28, Orifice drill to 3/32” (0.09375) ….compare to transgo 0.076, CK 0.110”
#27, if non-ECM valve train, Ck says to enlarge to 0.180 if upgrading to GN plate, pg. 112
#33, leave check ball (55N) out and drill small hole of 33 to 0.046” to prevent TV valve from sticking, see pg. 71 of atsg, dvd and transgo

Springs: ATSG pg. 75, 92. CK pgs. 102-112
304, use Sonnax 77968-01K tv plunger spring, (L 2.2”, W 0.490, wire .057), longer spring = later upshifts
316, 3-2 control valve spring, CK discards and replace with ¼” plug
319, line bias valve spring (use 700-R4 3-4 drum clutch spring, also Sonnax 77763-01) (TCI replaces with blocker rod, using a 1/8” roll pin ground down to .860 long)
321, accumulator valve spring (use 319 spring)
346, throttle valve boost spring, may not have one, make sure it does, CK pg. 11, 109
59, 1-2 Accumulator, use white 700-R4 spring, 1.766x1.685x0.170, ¼” nut over #76 pin for more tension, CK pg. 113
51, 3-4 accumulator use red spring, CK pg. 115

Always install the accumulator piston in the case before the spring, CK pg. 115
*61,59, may be omitted if ¼ checkball is tapped into feed hole (high performance), CK pg. 114

348, some vb’s have valve train, this vb not recommended, pg. 106
350, verify plug, clean orifice and keep
351, verify cup plug, pg. 107, remove to improve forced 2-1 shift kickdowns

True the gasket mounting surface and vb plate with wet stone, clean and dry.

Check balls: ATSG pg. 23, 71
OEM comes with 9 check balls below vb gasket
55D (2), 3rd accumulator
55E (6), Reverse/3rd
55F (4), 3rd clutch
55G (9), Lo/Detent
55H (10), Lo/Reverse
55J (1), 4th Accumulator
55K (7), Intermediate servo check ball in capsule…. CK pg. 125, 126, 141
55M (3), PT/D3
55N (5), TV exhaust, largest check ball….discard, CK pg. 141

55A, 55B, 55C, 3 checkballs on VB gasket, atsg pg. 77

Jakeshoe: You will use 5 checkballs in the case.
Rule of thumb on a 200-4R. If it's a bathtub it gets a checkball always. There are 4 in a line from front to rear. 2 small checkball locations and 2 bathtubs, install in the bathtubs, leave out of the small locations (3rd accum and 3-2 )

Air tests: applying 60 p.s.i. of compressed air
Direct clutch
Forward clutch
Center support
Overrun clutch assembly, air in the turbine shaft, CK pg. 47
4th clutch after assembly, CK pg. 137

Clearances: measure with feeler gauge or dial indicator
524, 525, Overdrive carrier pinion assembly, .009-0.024”, CK pg. 41
636, Front carrier assembly planet gear, 0.003-0.024”, CK pg. 80
661, Rear carrier assembly planet gear, 0.003-0.024”, CK pg. 90

615, Direct clutch, with feeler gauge 0.030-65”, CK pg. 62
(Apply-ring from older front clutch is taller and can be used in direct clutch if needed. Steels are 0.091”, May need to order thicker steel 0.100”)
628, Forward clutch, with feeler gauge 0.020-30”, CK pg. 70
631, Rear section end play, feeler gauge under snap ring, 0.002-.006” (compare to OEM 0.004-.025”)
629, Center section end play with dial indicator, after 530 is installed, 0.006-0.008”, CK pg. 134
(center end play must be greater than rear section, compare to OEM 0.020-.050”)
9, Front section end play, lift 503 input shaft
503 play minus 524 clearance = front section end play, 0.003-0.006”, CK pg. 139
Dvd clamps vice grips on top of stator shaft, turns trans upside down then uses feeler gauge
(compare to OEM 0.004-.030”)
524, feeler gauge under snap ring, CK pg. 47

601, Band clearance, servo, CK pg. 136

506, 4th gear clutch, not critical but must have some, CK pg. 137

Seals, Washers, Bearings, Bushings: ATSG pg. 94
O-rings and Seals
17, servo cover o-ring
18, servo inner seal
20, outer piston seal (servo)
22, inner piston seal
28, seals for servo apply pin (two)
33, rear housing oil seal
37, governor oil seal ring
40, electrical connector o-ring
46, case to housing reverse oil seal
50, 3-4 accumulator piston seal
52, solenoid o-ring
60, 1-2 accumulator piston seal
66, pan gasket
67, filter seal
201, front pump seal
204, pump slide ring
205, pump slide o-ring
210, pump slide seal support (orange color)
211, pump slide seal, black
502, turbine shaft o-ring
504, Turbine shaft solid ring
504, Turbine shaft scarf rings (two)
512, overrun clutch seals
535, 4th clutch seals (2, center support)
539, oil seals (3, center support shaft)
606, direct clutch piston seals
616, forward clutch shaft Teflon rings
621, forward clutch piston seals
648, lo/reverse piston seals
10, Pump to case ring seal ring
Dipstick o-ring

Thrust Washers
9, pump housing selective, affects front end play (yellow 0.188”)
531, internal gear support
541, support/direct clutch
617, direct/forward clutch
629, forward drum to output shaft selective, affects center end play (#13 0.128”)
631, rear selective, affects rear end play (#3 yellow 0.131”)
632, internal gear/rear
643, input drum/housing
662, rear carrier/internal gear

523, carrier/sun
528, carrier/internal gear
635, roller, internal gear/carrier
637, front carrier/sun
659, rear cam/lo race
663, sun/internal roller thrust

4, Stator shaft
202, pump body
509, overrun clutch, CK pg. 44
522, overdrive carrier
656, forward clutch housing
602, direct clutch, front
536, center support
540, center support
605, direct clutch, rear
634, front internal gear
641, rear sun gear
645, Lo/Reverse housing
660, rear carrier
32, rear case

Snap ring pliers
Small flat head screw driver
1-3/16 socket to remove tail housing bushing
Race driver set, old bushings and big washers of varying sizes
Table top press, Clutch spring compressor or c-clamps
Cobalt drill bits from 3/64, 1/16, 5/64, 3/32, 7/64, 1/8”

ATSG manual
CK performance manual
Haynes manual

39 Posts
Discussion Starter #13 (Edited)
I still have work to do. I haven't been able to get the air check for the band on the direct drum to work. Any suggestions?

39 Posts
Discussion Starter #14
I finished the 200-4R rebuild a while ago. Thank you to all that helped. Now I need to get my mind back into the project to finish the install. I'm going to use lock up. I need help with the following...

How to install lock up
What torque converter to buy for a daily driver, 350 engine
How to install the transmission to the crossmember

My crossmember was bolted to brackets that were welded on the frame. It is my understanding that the 200-4R transmission will sit a few inches further back compared to the original 2 speed. It will be difficult to cut the bracket off and re-weld without removing the bed. If I weld another bracket directly behind the original one that may not work well. Does anyone have pictures of their a-body with a 200-4R or 700-R4 mounted to the crossmember?

What recommendations do you have?
1 - 15 of 15 Posts